[Tomography guided biopsy for the diagnosis of pediatric pulmonary Cryptococcosis]

Pulmonary cryptococcosis is a lung infection caused by the Cryptococcus yeast. It is rare in pediatrics, especially in immunocompetent children. The diagnosis of pulmonary cryptococcosis can be challenging due to the low specificity of symptoms, low index of suspicion, and limited diagnostic resources.

To describe a clinical case of pulmonary cryptococcosis in an immunocompetent adolescent, detailing the diagnostic approach.

A 15-year-old patient, previously healthy, from a rural town, who consulted due to cough and a 1-month rib stitch pain, without fever or associated respiratory difficulty, with two images of condensation in the left lung on the chest x-ray. In the Computed Tomography, the images showed a nodular appearance. Due to suspicion of neoplastic pathology, a Positron Emission Tomography was performed, which showed hypermetabolic nodular lesions. The tomographic characteristics could correspond to fungal or granulomatous involvement. Considering the images and epidemiological risk factors such as rural origin and contact with bird droppings, the possibility of a mycosis was considered. A lung needle biopsy was performed under tomographic guidance. Cryptococcus neoformans was identified in the microbiology laboratory culture. The patient received treatment with itraconazole and fluconazole with good clinical and imaging response after 10 months of therapy and follow-up.

In immunocompetent patients with a nonspecific clinical presentation, images can guide the diagnosis of pulmonary cryptococcosis, and an etiological search is essential to confirm it. In our case, the CT-guided needle biopsy was of great diagnostic utility.