Showing posts with label Allergies. Show all posts
Showing posts with label Allergies. Show all posts

Wednesday 17 July 2024

Can you safely take Bumetanide or Acetazolamide (Diamox) if you have a Sulfonamide allergy?

I was contacted by a reader in Italy whose child with autism may respond to bumetanide, but has a sulfonamide allergy and got a skin reaction (hives). She had to stop giving the drug, but wanted to know how she could re-start bumetanide.

Other readers have pointed out how they dare not try bumetanide because they know their child has a sulfonamide allergy. I think our longtime reader Tanya is one example.


Key Point to Note

Most people discover their sulfonamide after being giving an antibiotic in early childhood.

It is now well established that many (but not all) people with an allergy to sulfonamide antibiotics can safely take a sulfonamide diuretic like Bumetanide or Diamox/Acetazolamide. This is presented in case studies later in this post.


Sulfonamide Drugs

Many common drugs are “sulfonamides”. Their chemical structure includes a sulfonyl (–SO2) group attached to an amine group (–NH2). They include common antibiotics, like erythromycin, many diuretics (bumetanide, furosemide, acetazolamide (Diamox), some anticonvulsants (zonisamide) and some anti-inflammatory drugs (sulfasalazine).


Sulfonamide Allergy

Many parents discover early in their child’s life that their child has a sulfonamide allergy. Sometimes this is abbreviated to a “sulfa allergy.”

The symptoms of a sulfonamide allergy can vary but may include:

  • Skin reactions (rash, hives, or itching)
  • Fever
  • Swelling
  • Respiratory issues (shortness of breath)
  • Anaphylaxis (in severe cases)

Usually the symptoms are minor, but once diagnosed the parents usually take note never to give their child any sulfonamide drug.


If you have the allergy must you avoid all sulfonamide drugs?

The standard assumption has been that if you have a sulfonamide allergy you cannot take Bumetanide or Acetazolamide (Diamox).

Upon further investigation in the research, this may not always be true.


What happens when there is no alternative drug?

When treating ion channel/transporter dysfunctions there may not be a non-sulfonamide alternative.

Acetazolamide (Diamox) is documented in the literature as a case in point. Bumetanide has not yet made it to the literature.

Furosemide fortunately has been researched and a safe desensitization protocol exists. Furosemide is a very similar drug to bumetanide.


Desensitization strategies

I did recently write about enzyme potentiated desensitization, which is an old, mostly overlooked, technique to overcome allergic reactions. I was interested in pollen allergy.

The best-known kinds of desensitization are allergy shots and more recently overcoming nut allergies, which gets media attention. 

Oral immunotherapy for peanut allergy in young children

The study also found that the youngest children and those who started the trial with lower levels of peanut-specific antibodies were most likely to achieve remission. 

“The landmark results of the trial suggest a window of opportunity in early childhood to induce remission of peanut allergy through oral immunotherapy,” says NIAID Director Dr. Anthony Fauci. “It is our hope that these study findings will inform the development of treatment modalities that reduce the burden of peanut allergy in children.”


I did wonder that if it works for nuts then why not bumetanide.

It turns out that I am not the first to consider desensitization to a drug allergy. The best known method is rapid drug desensitization (RDD), usually intravenous, which opens a window to be able to start taking a drug you are allergic to. Once you stop taking the drug, you then again become allergic to it.

The other approach is more like dealing with nut allergies, it is called slow drug desensitization (SDD) and involves taking a tiny initial dose and then slowly increasing it over weeks and months.

Drug desensitization is normally done in hospital as part of some therapy when you absolutely must have a drug that you are allergic to.

The paper below contains information on a very large number of common drugs where drug desensitization has been successfully carried out.


Desensitization for the prevention of drug hypersensitivity reactions

Drug desensitization is the temporary induction of tolerance to a sensitized drug by administering slow increments of the drug, starting from a very small amount to a full therapeutic dose. It can be used as a therapeutic strategy for patients with drug hypersensitivity when no comparable alternatives are available. Desensitization has been recommended for immunoglobulin E (IgE)-mediated immediate hypersensitivity; however, its indications have recently been expanded to include non-IgE-mediated, non-immunological, or delayed T cell-mediated reactions. Currently, the mechanism of desensitization is not fully understood. However, the attenuation of various intracellular signals in target cells is an area of active research, such as high-affinity IgE receptor (FcɛRI) internalization, anti-drug IgG4 blocking antibody, altered signaling pathways in mast cells and basophils, and reduced Ca2+ influx. Agents commonly requiring desensitization include antineoplastic agents, antibiotics, antituberculous agents, and aspirin/nonsteroidal anti-inflammatory drugs. Various desensitization protocols (rapid or slow, multi-bag or one-bag, with different target doses) have been proposed for each drug. An appropriate protocol should be selected with the appropriate concentration, dosage, dosing interval, and route of administration. In addition, the protocol should be adjusted with consideration of the severity of the initial reaction, the characteristics of the drug itself, as well as the frequency, pattern, and degree of breakthrough reactions.

Two categories of desensitization protocols are currently available: RDD and slow drug desensitization (SDD). RDD is recommended for immediate reactions, both allergic and nonallergic. The most widely used RDD protocol is doubling the dosage every 15 minutes until the therapeutic dose is achieved. SDD is recommended for type IV delayed hypersensitivity reactions with T cell involvement, and can be performed both orally and intravenously. There is as yet no consensus on SDD protocols, including the initial dose, dose increments between steps, and dosing interval. Further clinical experience and research are required to establish the role and efficacy of desensitization for delayed reactions.

H1 blockers, H2 blockers, and glucocorticoids can be used as premedication. Aspirin and montelukast block the end products of the arachidonic acid cascade and decrease the incidence and severity of BTRs. NSAIDs can help to control the symptoms of cytokine release syndrome. Glucocorticoids alone are not recommended because they cannot prevent the initial degranulation of mast cells. 

The desensitization process is known to be antigen-specific, as the level of drug-specific immunoglobulin E (IgE) decreases but the levels of other allergen-specific IgE remain consistent throughout the treatment period. However, the cellular and molecular mechanisms underlying drug desensitization are not yet fully understood.

Aspirin/NSAID desensitization is considered for patients with cardiovascular or musculoskeletal diseases who require aspirin or NSAID administration for prolonged periods.

The temporary tolerance to aspirin/NSAIDs lasts 48 to 72 hours after desensitization. Therefore, hypersensitivity reactions can recur 2 to 5 days after discontinuation if the therapeutic dose is not continued.


DHR to β-lactams, such as penicillin or cephalosporin, is more common than that to non-β-lactams. Desensitization can be performed for both immediate and delayed hypersensitivity reactions. The protocol should be selected based on patient characteristics, hospital capacity, and physician preferences. It is generally started with 1/1,000 of the therapeutic dose and then increased by 2 to 3-fold every 15 minutes to 5 hours. Oral administration is preferred due to its ease, safety, and effectiveness. Desensitization to penicillin and cephalosporins has been well established. Successful desensitization has also been reported for other β-lactams, such as carbapenem and monobactam, and non-β-lactams, such as vancomycin, clindamycin, metronidazole, macrolides, aminoglycosides, tetracycline, and ciprofloxacin.

Successful desensitization to other antimicrobials has also been reported for antifungals, such as amphotericin B, fluconazole, itraconazole, voriconazole, and micafungin, and for antivirals, such as acyclovir, valganciclovir, ribavirin, and nevirapine.


Furosemide desensitization

There is no literature specific to bumetanide but there is on the very similar drug furosemide.



Furosemide is a commonly used loop diuretic that contains a sulfonamide group. Although there are rare reports of hypersensitivity to furosemide, severe reactions, including anaphylaxis, have been reported. Ethacrynic acid, the only loop diuretic without a sulfonamide moiety, is no longer available in oral formulation, thus posing a dilemma in the outpatient treatment of patients with furosemide allergy.

Published protocols for furosemide desensitization include rapid intravenous administration and oral protocols lasting 3 to 10 days.3–5 The oral protocols were performed in patients with non–type I hypersensitivity reactions. We present a rapid, oral protocol for desensitization in a patient with presumed type 1 furosemide allergy manifesting as urticaria.


Desensitization to sulfonamide-containing antibiotics has been extensively used, but desensitization to furosemide is uncommon. The oral protocols previously described took 3 to 10 days and were performed in patients with non–type I hypersensitivity reactions, one with pancytopenia and the other with pancreatitis. The patient with a type I hypersensitivity reaction underwent an intravenous desensitization protocol. Rapid oral desensitization to a loop diuretic has not been previously described. The potential advantages of oral desensitization are that it is probably safer than intravenous desensitization, it may be more cost-effective in terms of monitoring and staff requirements, and it may be possible to perform in an outpatient setting. We propose our protocol as a novel approach to furosemide desensitization therapy for patients with non–life threatening reactions to furosemide. Further progress in the diagnosis and treatment of hypersensitivity to sulfonamide drugs will require identification of the major antigenic determinant and standardization of skin testing and specific IgE testing.

I think we should say good work to Dr Naureen Alim, then at Baylor College of Medicine Houston, Texas.

If anyone wants to desensitize to a bumetanide allergy I think she is the one to contact for advice. She is easy to find via Google. 

Here is another case example. 

Desensitization therapy in a patient with furosemide allergy

Allergy to furosemide is a rare phenomenon. Desensitization to this sulfa-containing drug has not been frequently performed. We describe a patient with severe congestive heart failure and type I allergy to furosemide. Because of the severity of her condition, we decided to use a rapid intravenous desensitization protocol. Following the desensitization, the patient was treated with intravenous and oral furosemide with a dramatic improvement in her clinical state. We suggest that rapid desensitization may be a safe and effective way of introducing furosemide to allergic patients for whom loop diuretics are urgently indicated.


In the case of Acetazolamide, here is one published desensitization method:


Desensitization to acetazolamide in a patient with previous antimicrobial sulfonamide allergy

Acetazolamide is a carbonic anhydrase inhibitor that is frequently used in the management of idiopathic intracranial hypertension. Acetazolamide is a sulfonamide agent; specifically, it is a non sulfonylarylamine, which lacks the amine moiety found at the N4 position that is seen in sulfa antibiotics. 

Sulfonamide antibiotics contain a substituted ring at the N1 position that is thought to be the driving factor in immediate hypersensitivity reactions.  

Although sulfa allergies are commonly reported, there is no evidence to suggest cross-reactivity between sulfonamide antibiotics and sulfonamide nonantibiotics. However, patients can report a history of allergy to both categories of drugs. We present a rapid desensitization protocol to acetazolamide in a patient with history of immediate hypersensitivity reactions to both a sulfonamide antibiotic and acetazolamide. 

We formulated a 12-step intravenous protocol that was performed in the intensive care unit setting (Table 1). Informed consent was provided by the patient, and she tolerated the procedure well without any adverse reactions. The desensitization procedure took 395 minutes or approximately 6.5 hours. She was monitored overnight in the hospital and was observed the following morning after taking 500 mg of acetazolamide orally to ensure tolerance. She was thereafter able to continue her recommended dose of acetazolamide without any issues to date.


Allergy to a sulfonamide antibiotic does not always mean you will be allergic to the non-antibiotic sulfonamide drugs.


Use of Acetazolamide in Sulfonamide-Allergic Patients With Neurologic Channelopathies

The 3 patients had been considered for carbonic anhydrase inhibitor treatment but a pharmacist had refused to fill a prescription for acetazolamide for 1 patient and the other 2 patients were denied treatment because of the allergy history. All 3 patients were prescribed acetazolamide and had no adverse reaction. Two patients improved substantially and are continuing treatment. A review of the pharmacology literature suggests that cross-reactivity between antibiotic and nonantibiotic carbonic anhydrase inhibitors is unlikely. Moreover, a review of case reports does not suggest cross-reactivity. Previous reports in the ophthalmology literature also indicate that acetazolamide can be administered to patients with a history of antibiotic sulfonamide allergic reaction.


These 3 cases confirm that the carbonic anhydrase inhibitor acetazolamide can be given to patients with a history of allergic skin rash with antibiotic sulfonamide.


Acetazolamide has been used for the treatment of episodic ataxia type 2, with benefit in 50% to 75% of patients. In episodic ataxia type 1, acetazolamide was also effective in decreasing attack frequency. Acetazolamide is also effective in the periodic paralyses. Carbonic anhydrase inhibitors have been used to prevent altitude sickness, to lower intraocular pressure in open-angle glaucoma, and to treat refractory absence, myoclonic, and catamenial epilepsy as part of multidrug regimens. Acetazolamide has recently been used for hemiplegic migraine and idiopathic intracranial hypertension. 

The lack of available clinical or pharmacological evidence to support cross-reactivity between sulfonamide antibiotics and acetazolamide lends supports to the use of acetazolamide to treat patients with episodic ataxia and periodic paralysis. Of our 3 sulfonamide-allergic patients, 2 improved in symptoms after treatment with acetazolamide and none of the 3 had a hypersensitivity reaction. We conclude that a sulfonamide allergy should not be a contraindication to treatment with acetazolamide in patients with neurologic channelopathies. 


Acetazolamide and sulfonamide allergy: a not so simple story

 Allergies and adverse reactions to sulfonamide medications are quite common. Two distinct categories of drugs are classified as sulfonamides: antibiotics and nonantibiotics. The two groups differ in their chemical structure, use, and the rate at which adverse reactions occur. Cross-reactivity between the two groups has been implied in the past, but is suspect. Acetazolamide, from the nonantibiotic group, is routinely used in the prevention and treatment of high altitude issues and may not need to be avoided in individuals with a history of sulfonamide allergy. This review addresses the differences between the groups and the propensity for intergroup and intragroup adverse reactions based on the available literature. We also examine the different clinical presentations of allergy and adverse reactions, from simple cutaneous reactions with no sequelae through Stevens-Johnson syndrome and anaphylaxis, with risk for significant morbidity and mortality. We offer a systematic approach to determine whether acetazolamide is a safe option for those with a history of allergy to sulfonamides.

Sulfonamide-containing antibiotics are the second most frequent cause of allergic drug reactions, after the b-lactams (penicillins and cephalosporins). In one large study, the incidence of reactions to trimethoprim–sulfamethoxazole (TMPSMX) was 3% of patients exposed, compared with 5% for amoxicillin. The incidence of reactions to nonantibiotic sulfonamides is not well established; it is clearly less than with antibiotics.


There are several approaches to the use of sulfonamide drugs (specifically acetazolamide) in patients with past reactions to this class of medications. The choice of strategy depends on the type and severity of the previous reaction, as well as the class of drug (antibiotic versus non antibiotic) and the risk–benefit profile for the patient. However, regardless of the approach, the risks of subsequent reactions cannot be completely eliminated, and a thorough discussion between the medical provider and the patient should include this point so that an informed decision regarding the use of acetazolamide can be made. The safest approach for the patient with any prior reaction to a sulfa drug, multiple drug allergies, or penicillin allergy would be to avoid all drugs in the sulfonamide group, including acetazolamide.


Avoidance of the entire sulfonamide drug group is warranted for individuals whose previous reaction included a serious and/or life-threatening condition such as anaphylaxis, SJS, and TEN. Any form of reexposure to the precipitating drug or a sulfonamide in the same group is strictly contraindicated. Published evidence has shown that SJS/TEN can recur with even minor reexposures and may be more severe in the second episode. Even though SJS/TEN reactions are so far not associated with nonantibiotic sulfonamides, because of the severity and life-threatening nature of these reactions, a safe practice is to avoid all sulfonamides in patients with past SJS or TEN from sulfonamide containing medications.


This paper was published in a journal on high altitude medicine. That is why the suggested alternatives are staged ascents of the mountain and oxygen.



The first key point is that you can have an allergy to sulfonamide antibiotics and have absolutely no negative reaction to sulfonamide drugs like bumetanide and acetazolamide (Diamox).

If you do have a mild allergic reaction to a sulfonamide drug, there are desensitization strategies that are proven to work in many people.

It looks like rapid oral desensitization to bumetanide and acetazolamide is likely possible, based on what has been shown possible with furosemide and a wide variety of other drugs.

Clearly the level of sensitivity and hence the nature of the allergic reaction can vary massively from person to person, this is why rapid desensitization usually takes place in hospital.

If you opt for the slower process, much less is known, because it is not generally used. If you did it in hospital it would require a very long stay and so would be hugely expensive.

It is suggested that slow drug desensitization (SDD) should be much more long lasting and hopefully might become permanent – as is the hope for nut allergy treatment.

When posed the initial question by our reader wanting to use bumetanide, I was thinking along the lines of slow drug desensitization (SDD), because this is how you would treat a pollen allergy. If rapid oral desensitization will work for taking bumetanide once a day that would be great. To maintain the protection from allergy it might be safer to take a small second daily dose.


Here is a quick overview of desensitization options for sulfonamide allergy:

  • Rapid Desensitization (RDD):
    • Faster process (hours)
    • Temporary tolerance achieved
    • May be repeated if needed
  • Slow Desensitization (SDD):
    • Slower process (days, weeks, or months)
    • Might offer a greater chance of longer-lasting
    • Still requires close monitoring

Important Considerations:

  • Always consult your doctor: They can assess your allergy severity, treatment options, and the suitability of desensitization if necessary.
  • Desensitization is not without risks: It requires careful monitoring.


I for one found this an interesting investigation and with promise for parents of those with severe autism who have been unable to trial Bumetanide due to a sulfonamide allergy. 

Hopefully our reader Dr Antonucci will follow up on this and make a bumetanide desensitization protocol for those people with autism and a sulfonamide allergy. Maybe he has already done it. It looks very achievable.

Wednesday 8 May 2024

Immunotherapy from the desert


Today’s post revisits the idea of using immunotherapies to treat autism.

Some readers of this blog are already doing this and a significant percentage of those are using IVIG.

Intravenous immunoglobulin (IVIG) is a pooled antibody, and a biological agent used to manage various immunodeficiency states and a plethora of other conditions, including autoimmune, infectious, and inflammatory states.

IVIG is not a precision therapy, it is more a case of when all else fails try IVIG.

In the United States it seems that many insurance companies will cover the cost of long-term IVIG therapy. In other countries the cost greatly limits the use of this therapy.

An interesting observation is that IVIG products can vary significantly in their potency, depending on where they are made. Several readers of this blog have noted this.

I attended the Autism Challenges and Solutions conference recently in Abu Dhabi. I did have a chat with Laila Alayadhi, a researcher and clinician from Saudi Arabia who has been publishing papers about autoimmunity in ASD for decades. She also published a series of studies that examined the potential of camel milk as a therapy. She examined both changes in biological markers of oxidative stress and inflammation as well as measures of autism severity.

Her most recent study is here:-


Comparative Study on the Ameliorating Effects of Camel Milkas a Dairy Product on Inflammatory Response in Autism Spectrum Disorders

The link between nutrition and autism spectrum disorder (ASD), as a neurodevelopmental disorder exhibiting impaired social interaction, repetitive behavior, and poor communication skills, has provided a hot point of research that might help use nutritional intervention strategies for managing ASD symptoms. This study examined the possible therapeutic potency of raw and boiled camel milk in reducing neuroinflammation in relation to behavioral characteristics. A blinded study was conducted on 64 children with autism (aged 2–12 years). Group I (n = 23) consisted of children who received raw camel milk; Group II (n = 27) comprised children who received boiled camel milk; and Group III (n = 14) comprised children who received cow milk as a placebo. Changes in plasma tumor necrosis factor-alpha (TNF-α) as pro-inflammatory cytokine in relation to behavioral characteristics evaluated using the Childhood Autism Rating Scale (CARS), Social Responsiveness Scale (SRS), and gastrointestinal (GI) symptoms before and after 2 weeks of raw and boiled camel milk therapy. Significantly lower plasma levels of TNF-α were recorded after 2 weeks of camel milk consumption, accompanied by insignificant changes in CARS and significant improvements in SRS and GI symptoms. Alternatively, Group III demonstrated an insignificant TNF-α increase without changes in CARS, SRS, and GI symptoms. This study demonstrated the positive effects of both raw and boiled camel milk in reducing neuroinflammation in patients with ASD. The improvements in the SRS scores and GI symptoms are encouraging. Further trials exploring the potential benefits of camel milk consumption in patients with ASD are highly recommended.



Apparently camel milk tastes just fine, although Dr Alayadhi told us she had never tried it prior to her research. She has shown than both pasteurized and raw milk are equally effective. I did ask her about other types of milk like goat’s milk and she said they had tried other milks and that only camel milk has shown the immunomodulatory effect.  When asked how much you need to drink, the answer was three glasses a day.

The Dentist

I did chat to another Saudi professor, a pediatric dentist, who gave a presentation about treating children with ASD.  Having had some pretty bad experiences with getting dental treatment and then overcoming them, I did feel I had something in common with Ebtissam Murshid.  I did catch up with her later and shared details of the D-Termined program created by US dentist David Tesini. It is a video training program for dentists how to treat kids with autism. I have written about it previously in this blog. Tesini very much tries to make the visit to the dentist fun, with lots of distractions in his treatment room. Murshid purposefully has blank white walls, believing that autistic kids get upset by bright colors and patterns. Hopefully she watches Tesini’s videos.

Murshid has published a book to help parents prepare their children for their trip to the dentist and, like Tesini, had made a small trial to show that her method is effective.

Some dentists are naturally good at treating the most difficult kids, but most are not.  It is impossible to predict.

A really good dentist needs neither restraint, like a papoose board, or sedation. If general anesthetic is needed, then something is not being done right. Kids with severe autism can be treated with local anesthetic just like other kids, they just need to go through a familiarization training like Tesini/Murshid use.


Back to immunotherapy

I did have many conversations with Carmello Rizzo who is an Italian doctor interested in both diet and autoimmunity to treat autism. He is a feature at many autism conferences and is a great speaker. He was telling me about Enzyme Potentiated Desensitization (EPD), an overlooked way to treat allergy care.

EPD was invented in the 1960s by a British immunologist Dr Len McEwen, at St. Mary’s Hospital, Paddington. EPD is approved in the United Kingdom for the treatment of hay fever, food allergy and intolerance and environmental allergies.

It is an unlicensed product (i.e. not a drug), it is available only on a “named patient” basis.

EPD is not the same as allergy shots.

Allergy shots, also known as allergy immunotherapy, are injections used to treat allergies over a long period of time. They work by gradually desensitizing your body to the allergens that trigger your allergy symptoms.

Allergy shots typically involve two phases, buildup and maintenance.

It is an escalating dose immunotherapy, when you gradually increase the exposure level of the identified allergen.

The buildup phase lasts for 3 to 6 months. You receive shots 1 to 3 times a week. The doctor will gradually increase the amount of allergen in each shot to help your body build tolerance.

In the maintenance phase you need shots less frequently, usually about once a month. This phase can continue for 3 to 5 years or even longer depending on your progress.

I was never interested in allergy shots because there are so many injections needed.

I found EPD of interest because you take just two shots a year and the effect may potentially control the allergy after 2 or 3 years.

EPD is not expensive and I suppose that is why nobody wanted to invested the tens of millions of dollars to get approval by the FDA. It remains approved for use in the UK, which is ultra conservative when it comes to medicines.

Carmello Rizzo is offering EPD in Italy and elsewhere.


Gene therapy for autism?

I did go to a presentation with an interesting title:

Developing effective therapeutics for Autism Spectrum Disorder

It was not really what I was expecting. It was a young MIT researcher talking about the potential to develop gene therapies to replace mutated genes with a new ones. They are doing this in a model of autism caused by a mutated copy of the SHANK3 gene.

I called him Dr Viral Vector and did have a chat with him. The most interesting thing about his technology is that not only can he target a specific type of cell, but he can target a specific part of the brain, or indeed any part of the body.

At the moment they inject a virus carrying the new gene directly into the brain. That is not going to go down so well with human subjects. The next stage is to try injecting the virus into a vein.

I did talk about the two gene therapies for Rett syndrome now in human trials in my presentation. The ultimate problem is the likely $3 million cost. 

You can use gene therapy as an immunotherapy. 



At the conference I was asked about a gene called DCLRE1C, it encodes the DCLRE1C protein, also known as Artemis.


Artémis (Diane), the huntress. Roman copy of a Greek statue, 2nd century. Galleria dei Candelabri

Source: By Jean-Pol GRANDMONT - Own work, CC BY-SA 3.0,


The Artemis protein is named after the Greek goddess Artemis, who was associated with the hunt, wilderness, wild animals, childbirth, and protection. This connection likely comes from the crucial role Artemis plays in DNA repair, which is essential for maintaining the integrity of the genetic material, like a protector safeguarding the building blocks of life.

Complete loss of function in DCLRE1C typically causes severe combined immunodeficiency. This is called Artemis-deficient severe combined immunodeficiency (ART-SCID).

Fortunately many possible mutations only partially impair the function of the DCLRE1C gene. They can lead to a spectrum of conditions, including atypical SCID, Omenn syndrome, Hyper IgM syndrome, and even just antibody deficiency. These conditions may have milder symptoms compared to classic SCID.

IVIG is a beneficial therapy for immunodeficiency; but is very expensive and not curative.

Humans all have 2 copies of the DCLRE1C and it is theoretically possible to increase expression of the good copy. But that is another story.


A gene therapy already exists for full-on ART-SCID.

Lentiviral Gene Therapy for Artemis-Deficient SCID

Why not use it in less severe cases?

The problem is going to be money, both for a lifetime on IVIG or a “hopefully” one-off gene therapy.

One lady in the audience of my talk had herself taken an expensive gene therapy and was not impressed.


Other interesting presentations

Pierre Drapeau from McGill University spoke about trying to repurpose a cheap old drug, called Pimozide, to treat motor neuron disease /ALS.  This was interesting because the process is similar to repurposing a drug for autism.

Pimozide is an old antipsychotic drug and it seems to work in ALS through its effect on a type of calcium channel called the T-type. Yes, just as in much autism, calcium channels are misbehaving.

The drawback of Pimozide is that it also blocks dopamine receptors in the brain, which is good if you have Tourette’s, but if you have ALS you then get symptoms of Parkinson’s as a side effect.

The solution is to tinker with the molecule and find a version (an analog) that will do the business with the T channels without causing tremors.  It looks like, via trial and error, this is nearly solved.

The whole process has already been going on for many years, it will take many more.

Life expectancy with ALS is only 2-5 years and they struggle to find test subjects in Canada. It looks like they may do trials in China.


An eye opener

A presentation with a very hard to digest title was also an eye opener. You can take a picture of the cornea in your eye and accurately diagnose all kinds of disorders. They started with peripheral neuropathy in diabetics and most recently moved on to people with autism. Using artificial intelligence (AI) they can now make a diagnosis just based on the nerve loss they observe in the cornea. They also can potentially measure the effect of therapies by the regeneration of those nerve fibers.  This is really clever. When Rayaz Malik started down this path, all the neurologists thought he was mad. Many years later and corneal confocal microscopy is widely used around the world, but not yet for autism diagnosis.

Antonio Persico is a well known autism clinician, he appeared virtually. He was mainly talking about antipsychotics. I had expected rather more. 



Immunotherapy addresses one of the four problem areas in autism. There cannot be a one size fits all approach, but you can certainly try camel milk. Addressing food allergy and intolerance is relatively straightforward and you do not need any fancy expensive genetic testing, as Carmello Rizzo pointed out.

There are people for whom genetic testing and/or a spinal tap opens the door to a precise diagnosis and hopefully treatment. That proved to be an unexpected controversial issue in my presentation.

My talk at the conference was all about using personalized medicine to treat autism. The organizer of the event reads this blog and knows that I am rather an outsider, since I am more in treating autism than just researching it.

I had a two and a half hour time slot and I made sure to use it all. 

Advances in Personalized Medicine to Treat Autism

I should mention that I also had some long conversations with Paul Shattock, who pretty much founded the gluten and casein free diet years ago, back at the University of Sunderland. If you are interested in the history of autism, he is a great person to talk to. He is nearly 80 years old, but still has a sharp sense of humour. He has stumbled into more than his fair share of controversies. In Abu Dhabi his opinions and observations were widely shared by other speakers. One younger American speaker thought his views were dangerous; had he taken the time to talk to Paul, he would have found them pretty well thought out. I did ask Paul what has happened to his old friend Andew Wakefield – apparently making another film.



Tuesday 16 January 2018

How much Histidine? Dermatitis and FLG mutations

Today’s post is not about autism, it is about allergy and atopic dermatitis in particular.
Many people are affected by atopic dermatitis (AD), also known as eczema; it is particularly common in those with autism. Children who develop asthma have often first developed atopic dermatitis (AD).
Atopic Dermatitis is another of those auto-immune conditions and the sooner you stabilize such conditions the better the prognosis.

Skin therapies from a company
spun-off from Manchester University

A while back on this blog I was looking at the various amino acids and came across the observation that histidine, a precursor of histamine, appears to be a mast cell stabilizer. Mast cells are the ones that release histamine and IL-6 into your blood. Histamine then does on the trigger yet more IL-6 to be produced.  IL-6 is a particularly troublesome pro-inflammatory cytokine.
At first sight giving a precursor of histamine to people who want less histamine seems a crazy thing to do, but plenty of people report their allergies improving after taking histidine. As we have discovered, feedback loops are very important in human biology and these can be used sometimes to trick the body into doing what you want it to do. Having a higher level of histidine in your blood might make histamine production easier but it might also be telling the body not to bother, or just to delay mast cells from degranulating.  Whatever the mechanism, it does seem to work for many people. 

How Much Histidine?
Most histidine pills are 0.5g and it appears people use about 1g to minimize their allergy. 1g is the dose Monty, aged 14 with ASD, has been using during the pollen allergy season.
My sister recently highlighted a new "high tech" OTC product for skin conditions, Curapella/Pellamex, its main ingredient is histidine and it is a lot of histidine, 4g.

The company that produces the supplement have teamed up with the Universities of Edinburgh and Manchester to make a clinical trial, which is featured below.
They are considering the interaction between histidine and filaggrine (produced by the FLG gene). 

Mutations in the FLG gene are associated with atopic dermatitis and indeed with asthma, hay fever, food allergies, and, rather bizarrely, skin sensitivity to nickel.
In effect it is suggested that histidine makes filaggrine work better and thus atopic dermatitis and some other skin conditions will improve.  

Atopic dermatitis (AD), also known as eczema, is one of the most common chronic skin conditions worldwide, affecting up to 16% of children and 10% of adults. It is incurable and has significant psychosocial and economic impacts on the affected individuals. AD etiology has been linked to deficiencies in the skin barrier protein, filaggrin. In mammalian skin, l-histidine is rapidly incorporated into filaggrin. Subsequent filaggrin proteolysis releases l-histidine as an important natural moisturizing factor (NMF). In vitro studies were conducted to investigate the influence of l-histidine on filaggrin processing and barrier function in human skin-equivalent models. Our further aim was to examine the effects of daily oral l-histidine supplementation on disease severity in adult AD patients. We conducted a randomized, double-blind, placebo-controlled, crossover, nutritional supplementation pilot study to explore the effects of oral l-histidine in adult AD patients (n=24). In vitro studies demonstrated that l-histidine significantly increased both filaggrin formation and skin barrier function (P<0 .01="" respectively="" span="" style="background: yellow; margin: 0px;">Data from the clinical study indicated that once daily oral l-histidine significantly reduced (P<0 .003="" 34="" 39="" 4="" ad="" after="" and="" assessment="" by="" disease="" eczema="" measure="" of="" oriented="" patient="" physician="" scoringad="" self-assessment="" severity="" span="" the="" tool="" treatment="" using="" weeks="">. No improvement was noted with the placebo (P>0.32). The clinical effect of oral l-histidine in AD was similar to that of mid-potency topical corticosteroids and combined with its safety profile suggests that it may be a safe, nonsteroidal approach suitable for long-term use in skin conditions that are associated with filaggrin deficits such as AD. 
In this paper, we suggest that a simpler, nutritional supplementation of l-histidine may have a beneficial potential in AD.

l-histidine is a proteinogenic amino acid that is not synthesized by mammals. In human infants, it is considered “essential” due to low levels of histidine-synthesizing gut microflora and minimal carnosinase activity, which helps in releasing free l-histidine from carnosine.24 Our interest in the use of l-histidine in AD was stimulated by several observations. Firstly, in both infants and adults, a histidine-deficient diet results in an eczematous rash.25 In rodents, 3H-histidine is rapidly (1–2 hours) incorporated into profilaggrin within keratohyalin granules after intraperitoneal or intradermal injection14,26 and within 1–7 days is released as a free NMF amino acid in the upper stratum corneum.14 Furthermore, reduced stratum corneum levels of free NMF amino acids, including histidine and its acidifying metabolite urocanic acid (UCA), are associated with AD disease severity and FLG genotype.27,28

Given this evidence for the dependence of filaggrin processing and NMF formation on suitable levels of l-histidine, we hypothesized that l-histidine would both enhance filaggrin processing in an in vitro, organotypic, human skin model and have beneficial effects as a nutritional supplement in subjects with atopic dermatitis. 

After a 2-week wash-out period in which subjects were asked not to use any medicinal product for their AD, the same measures were repeated and patients were provided with identical sachets containing either 4 g l-histidine (Group A) or 4 g placebo (erythritol); Group B) which was taken once a day, dissolved in a morning fruit drink.  


It looks like 4g of histidine has the same potency as mild topical steroid creams, when treating atopic dermatitis.
The big problem with topical steroids is that you can only use them for a week or two. It you use them for longer, you end up with a bigger problem than the one you were trying to treat.
The 4g a day of histidine is put forward as a safe long term therapy.
Is the mode of action related to mast cells or filaggrin (FLG)? Or perhaps both?
If 1g of histidine does improve your allergies, perhaps you should feel free to try a little more.
You can buy histidine as a bulk powder. Pellamex is quite expensive, particularly if more than one family member is affected, as you would expect to find in a genetic condition.