Differential Diagnosis, investigations, and treatment
Differential diagnosis included hyper-IgE syndrome, common variable
immunodeficiency, hyper IgM syndrome, and other primary immunodeficiency
diseases. Workup demonstrated hypereosinophilia of 3.9
K/mm3 (0-0.6 K/mm3) and elevated IgE
1521 IU/mL (3-423 IU/mL) with normal levels of IgG, A, and M. Her
antibody responses to pneumococcal, diphtheria and tetanus antigens were
adequate. Lymphocyte subsets showed slightly low absolute CD3 and CD4
count, with normal absolute B cells and NK cells. Mitogen proliferation
assays to Phytohemagglutinin, Concanavalin A, and Pokeweed antigens were
normal, suggestive of adequate T-cell function.
A next generation sequencing NGS gene panel for inherited immune
dysfunction syndromes showed a variant of unknown significance in key
immune regulator of PGM3 , including a heterozygous missense
mutation c.337C>G (p.Pro113Ala) on exon 4. Other genes that
can lead to HIES-related diseases were negative: TYK2, DOCK8,
STAT3, IL6, IL6ST, IL6R, ZNF341, TGFBR1, TGFBR2, SPINK5, CARD11 .
She later developed recurrent wheezing responsive to asthma treatment at
4 months old and multiple blinking spells concerned of seizures at 10
months old. Between ages of 1-2, she had two bacterial pneumonia, one
required hospitalization. The recurrent eczema flares were unresponsive
to initial treatment of topical 0.1% triamcinolone and 2.5%
hydrocortisone, antihistamine, emollient, bleach baths, and wet wraps.
She also received topical mupirocin for impetiginization. At the fourth
months mark since first hospitalization, betamethasone 0.05% ointment
and 1mg/kg of prednisolone daily were initiated, which only resulted
partial response. At the end of six-month period, dupilumab was
initiated with a loading dose of 120mg (12mg/kg) and maintenance dose of
60mg (6mg/kg) every four weeks.