Spotting immunodeficiency in the pediatric dermatology clinic
This story appears courtesy of MDedge News
EXPERT ANALYSIS FROM COASTAL DERM
SEATTLE – Immunodeficiency in children can look much like eczematous dermatitis. Be aware of this potential diagnosis.
“Although it is important to know these are extremely rare conditions, you don’t want to miss them because you can literally change that child’s life,” Markus Boos, MD, an assistant professor of pediatrics at the University of Washington, Seattle, said in an interview at the annual Coastal Dermatology Symposium.
He outlined some key clinical features and patient history that can raise a potential red flag.
“Many primary immunodeficiencies present with a scaly red rash, but these can often be distinguished if you take a thoughtful history, and you really spend time looking at the morphology and distribution of the rash,” Dr. Boos said.
The distribution of the rash also can be distinctive. For example, hyper-IgE syndrome shows up as little red pus bumps that are widespread, but specifically occur on the face and other areas that usually aren’t affected eczematous dermatitis. “You should really focus on that, and not just assume that because something [like eczematous dermatitis] is common, everything has to be that,” Dr. Boos said at the meeting, which was jointly presented by the University of Louisville and Global Academy for Medical Education.
He also warned about a false positive. You may be alerted to high eosinophil and high IgE levels determined by a primary care physician’s tests, but these aren’t necessarily a strong indicator of hyper-IgE syndrome, he said. “Many inflammatory conditions in children have high levels of both those, so they aren’t a distinguishing feature of any one of them. You can reassure a family that the child doesn’t necessarily have hyper-IgE syndrome. There’s this leap [people take] because it sounds like the name, but it’s not a very specific marker of that particular condition.”
Patient history of an immunodeficiency patient in general obviously can include a history of infections, although a high rate of ear infections is pretty typical among children. The key is to ask yourself: “At what point does it seem like something that is beyond normal?” Dr. Boos said. Infections that required hospitalizations or were invasive or required antibiotics all are potential clues. Other factors to consider include growth and development issues such as frequent diarrhea or failure to thrive, or family members with frequent infections or who died prematurely.
Hyper-IgE patients also may have a prominent forehead and chin, deep-set eyes, broad nose, thickened facial skin, or a high arched palate. These physical features become more prominent by adolescence. For a reference for physical features go to https://primaryimmune.org/about-primary-immunodeficiencies/specific-dise....
Clinical features of various immunodeficiencies include the following:
- Papulopustular eruption with frequent infections and musculoskeletal changes. This presentation is suggestive of autosomal dominant hyper-IgE syndrome. These children have a “heterozygous mutation in the gene encoding the transcription factor STAT3,” according to the Immune Deficiency Foundation.
- Severe atopy with extensive warts/molluscum/herpes simplex virus. This presentation is suggestive of autosomal recessive hyper-IgE syndrome. These children have “mutations and deletions in the DOCK8 gene,” the Immune Deficiency Foundation asserts.
- Diffusely red baby. Consider immunodeficiency if the patient also has experienced failure to thrive and/or diarrhea, or has a history of infection. High IgE levels are not a strong signal of hyper-IgE syndrome.
- Severe eczematous (or psoriasiform) dermatitis with chronic diarrhea, failure to thrive, and diabetes or hypothyroidism. This presentation is suggestive of IPEX syndrome (immune dysregulation, polyendocrinopathy, enteropathy, X-linked).
- Atopic dermatitis with bloody diarrhea, thrombocytopenia, recurrent ear infections. This presentation is indicative of Wiskott-Aldrich syndrome.
Dr. Boos is personally familiar with primary immunodeficiencies because he works closely with an immunology clinic, which also means he has a lot of support. Most clinicians diagnosing these patients don’t. If you find yourself with a case, “call in the troops,” he advised. You should be connected to a rheumatologist when there’s evidence of autoimmune disease, and hematologists or oncologists for the treatment, which requires a bone marrow transplant in the case of autosomal recessive hyper-IgE syndrome. Otherwise treatment is largely supportive for this immunodeficiency.
Having that network can be invaluable in managing what can be a very complicated patient. “If you ever feel uncomfortable making a decision about their care, discussing it with those other providers can give you some peace of mind,” he said.
Dr. Boos disclosed that he is a clinical researcher for Regeneron. This publication and Global Academy for Medical Education are owned by the same parent company.
By Jim Kling