Insights into pulmonary lophomoniasis infection in a Bruton's disease patient; A case report study and literature review.

Introduction: Lophomonas infection is a rare respiratory illness caused by parasites, mostly reported in immunocompromised patients. X-linked agammaglobulinemia (XLA), or Bruton's disease, is a primary immunodeficiency caused by a defective Bruton's tyrosine kinase (BTK) gene. This defect results in a deficiency or absence of functional BTK protein, leading to significantly reduced or absent B lymphocytes and serum immunoglobulin levels. Case presentation: A 21-year-old male patient was admitted to our service exhibiting a six-week history of fever, dyspnea, and productive cough. The patient's condition deteriorated despite prior outpatient management. Following abnormal laboratory values and computed tomography, bronchoscopy was performed. Microscopic evaluation of the bronchoalveolar lavage fluid revealed the presence of viable, oval-shaped, flagellated Lophomonas protozoa. Conclusion: In evaluating immunocompromised patients with sustained respiratory symptoms, clinicians should consider opportunistic infections, such as pulmonary lophomoniasis, in their differential diagnosis. Delayed intervention in this patient population may lead to irreversible adverse sequelae.