TAP deficiency syndrome
Patients with TAP deficiency syndrome typically present with recurrent bacterial infections of the upper respiratory tract (chronic purulent rhinitis, sinusitis, otitis media) within the first 6 years of life. This is followed by recurrent bacterial infections of the lower respiratory tract (bacterial pneumonia, chronic bronchitis, and subsequent bronchiectasis) and skin (necrotizing granulomatous lesions) within the second decade of life. Common culprits include both gram positive (Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenzae) and gram negative (Klebsiella, Escherichia coli, Pseudomonas aeruginosa) organisms. Early age of onset and a positive family history can be additional diagnostic clues.
If left untreated, recurrent respiratory infections with subsequent bronchiectasis and progressive respiratory failure may significantly increase morbidity and mortality. Septicemia is an additional complication.
D81.6 – Major histocompatibility complex class I deficiency
725136003 – Immunodeficiency by defective expression of human leukocyte antigen class 1
Differential Diagnosis & Pitfalls
- (GPA, formerly Wegener granulomatosis) can also present with necrotizing granulomatous inflammation of the skin and upper respiratory tract, but, unlike TAP deficiency syndrome, GPA classically also affects the kidneys, leading to hematuria with red cell casts on evaluation. Positivity for cytoplasmic antineutrophil cytoplasmic autoantibodies (c-ANCA) / proteinase 3 (PR3)-ANCA can also be used to differentiate this condition.
- (CGD) can also present with cutaneous and respiratory granulomatous inflammation, and affected individuals have increased susceptibility to infection with catalase positive organisms. An abnormal dihydrorhodamine test or nitroblue tetrazolium dye reduction test can be used to diagnose this condition.
- (CVID) involves defective B cell differentiation and subsequent decreased plasma cell formation and immunoglobulin synthesis. CVID can also present with recurrent bacterial respiratory and cutaneous infections. Flow cytometry for HLA expression and serum electrophoresis can be used to differentiate this condition.
- – Omphalitis, delayed separation of the umbilical cord stump at birth, recurrent otitis media, perirectal abscesses, bacterial sepsis, and necrotizing ulcers resembling pyoderma gangrenosum.
- Nocardiosis (see , )
- – Sweat chloride concentration would not be elevated in TAP deficiency syndrome and can be used to differentiate this condition.
- (PG) is a diagnosis of exclusion.