INTRODUCTION: Morbidity is defined as the occurrence of disease, symptoms of disease, or the proportion of disease in a population. X-linked agammaglobulinemia is a rare and underdiagnosed inborn error of immunity, leading to delayed diagnosis and treatment.
CASE PRESENTATION: A 12-year male with a history of recurrent respiratory infections, 2 pneumonias, refractory otitis media, and 5 episodes of serious infections requiring parenteral antibiotics last year, presented with absent tonsillar tissue, raising suspicion of an inborn error of immunity. Laboratory results IgA -25.6, IgE -18.30, IgG 521, IgM -16.9, CD3 lymphocyte subset 95% (reference 58-80%), absolute CD3 count 2343 (reference 920-2200), CD4 38% (reference29-52%), absolute CD4 count 915 (reference 520-1440), CD4/CD8 ratio 0.7 (reference 1.0-2.8), CD16+CD56 NK cells 4% (reference 3-19%), absolute CD16+CD56 NK cell count 97 (reference 70-500), CD19 1% (reference 2-34%), and absolute CD19 count -20 (reference 200-820). Chest CT revealed lung calcifications, atelectasis, and bronchiectasis, raising suspicion of X-linked agammaglobulinemia. Treatment: IV immunoglobulin G, clarithromycin, and MART therapy initiated.
DISCUSSION: X-linked agammaglobulinemia is an inborn error of immunity caused by a mutation in the BTK gene, which is involved in the maturation of B lymphocytes, leading to reduced or absent immunoglobulins and increased susceptibility to recurrent infections, mainly affecting the respiratory and digestive tracts. Physical examination often reveals extremely small or absent tonsils, adenoids, and cervical lymph nodes. Delayed diagnosis leads to recurrent respiratory infections, resulting in increased morbidity such as bronchiectasis, bronchial wall thickening, and interstitial lung disease.
CONCLUSION: The mortality rate in patients with X-linked agammaglobulinemia is 17%, with 38% of cases associated with irreversible lung injury, bronchiectasis, significantly reducing their survival. Timely diagnosis through detailed medical history, physical examination, relevant laboratory studies, and initiation of replacement therapy have reduced the morbidity and mortality associated with this condition, increasing the life expectancy of these patients.”