Q:

7/2/2013
46 year-old female RN started having recurrent furuncle/abscess on almost her entire body approximately 4 weeks after her first baby was born 15 years ago. In her infectious disease physician’s mind, these are “the worst skin infections” he has seen. They required multiple incision and drainage with numerous courses of oral and intravenous antibiotics. A few cultures from the wound showed MRSA. In addition, she also reports 4 cases of pneumonia in her life. This first one happened after she had her first baby for which she was hospitalized for 3 weeks.

Finally, 3 years ago, she was referred to an allergist and was diagnosed with PID - selective IgG deficiency. She was put on monthly IVIG. Since then, she has experienced “significant” improvement of her skin infection. This means a reduction in the frequency of recurrence, reduction of number of boils from each flare-up and severity of each boil. She also reports there is no need for intravenous antibiotics for each flare as oral antibiotic seems to be working. She reports no more “Pneumonia” while she was on monthly IVIG. She has never had frequent OM, sinusitis, or bronchitis. She denied joint pain, swelling, or stiffness. She was diagnosed with Hashimoto thyroiditis 10 years ago and then she was told she had a goiter for which she had a thyroidectomy in 2005. She denied chronic diarrhea.

Now she is concerned that she may have “side effects” from IVIG Gammagard as she always develops a headache the same night IVIG is given, which usually lasts about 3-4 days then disappears on its own. She also feels “drained” with tiredness for a few days after IVIG. All her available labs were reviewed. The only low immunoglobulin are IgG2 at 187 (241-700 mg/dl) and IgG3 at 15 (22-178 mg/dl) (an example from Oct., 2010). Her repeat lab in May, 2013 shows only Ig3 is low at 18 (22-178). All others are normal except streptococcus pneumonia shows 7/14 (50% >2.0 mcg/ml) serotype are protective against invasive pneumococcal disease. My questions are:

1. I don’t think the low IgG2 and IgG3 can explain her skin infections – recurrent MRSA furunculosis; do you agree?

2. Did we miss anything in her case for diagnosis? Should we perform more tests for innate immune disorder? I think her cellular immune function is good.

3. If the replacement of immunoglobulin is medically necessary, will it be better to switch her to subcutaneous injection?

4. If the replacement of immunoglobulin is continued, how should we monitor her? Her persistent low Ig3 despite IVIG indicates a need for increasing her current dosage?

A:

Thank you for your inquiry.

Unfortunately, I am not going to be able to give you a definitive response to your inquiry, and thus I am going to ask for help from Dr. Francisco Bonilla, who is a world-recognized expert in immunodeficiency disorders. I will forward you Dr. Bonilla’s response as soon as we receive it.

Thank you again for your inquiry.

Sincerely,
Phil Lieberman, M.D.

We received a response from Dr. Francisco Bonilla. Thank you again for your inquiry.

Sincerely,
Phil Lieberman, M.D.

Response from Dr. Francisco Bonilla:
1. I assume the numbers in your email are after she started IVIG. In that case, the subclass levels do not matter at all, they are irrelevant. The same is true of pneumococcal antibody levels.
 
2. I am unable to answer clearly about the diagnosis since I do not have the full data from the evaluation before IgG therapy. In any case, recurrent pustulosis is a very unusual presentation of antibody deficiency. I think it is more likely that she has staph colonization and eradication of that would be more effective.
 
3. If you feel IgG therapy is still indicated, there is no reason not to try subcutaneous infusion.
 
4. Monitoring is difficult for the subclass deficiency indication which is controversial anyway. I would dose by weight and clinical response. Start at 0.5 g/kg monthly equivalent.
 
Francisco A. Bonilla, MD, PhD
Boston Children's Hospital

AAAAI - American Academy of Allergy Asthma & Immunology