Background: Pneumocystis jirovecii primarily causes pneumonia in immunosuppressed individuals, particularly those living with advanced HIV/AIDS. Extrapulmonary dissemination is uncommon, with bone marrow involvement described in only a handful of cases globally. Bone marrow infection occurs in the setting of severe immunosuppression, poses diagnostic challenges, and carries a high mortality rate. Methods: We describe the case of a 34-year-old man newly diagnosed with HIV/AIDS, presenting with severe immunosuppression and Pneumocystis jirovecii pneumonia. The patient initially improved with cotrimoxazole and corticosteroids, but was readmitted shortly after discharge with abdominal pain, diarrhea, and worsening pancytopenia. A bone marrow biopsy revealed Pneumocystis jirovecii cysts, confirming disseminated infection. Concomitant Kaposi sarcoma involving the skin and gastrointestinal tract was also diagnosed. Despite antimicrobial therapy, the patient’s condition worsened, leading to multisystem organ failure and death two months later. Conclusions: This case highlights a rare presentation of disseminated Pneumocystis jirovecii infection with bone marrow involvement in a patient with advanced HIV/AIDS. Although infrequent, this complication should be considered in individuals with Pneumocystis jirovecii pneumonia who develop persistent cytopenias and systemic symptoms. Diagnosis depends on histopathologic confirmation, which may lead to under-recognition. Early suspicion and individualized management are essential, though the optimal treatment approach for extrapulmonary infection remains undefined.

Transient CD4 lymphocytopenia is defined as the transitory presence of CD4+ T lymphocyte fewer than 300 cells/mm³ or less than 20% of T cells without HIV infection. It can occur due to multiple causes; however, it is rare for it to occur due to opportunistic infections. Few cases have been described in the literature where antimicrobial treatment normalizes the CD4 count, being more frequent in Mycobacterium tuberculosis infections. To date, this phenomenon has not been described in Cryptococcus neoformans infections. This would be the first reported case according to our knowledge, of a patient who normalizes CD4 count after antifungal treatment, later developing alveolar proteinosis due to M. Tuberculosis.

Introduction: Studying the prescription of last generation antibiotics helps to identify the causes and consequences of the inadequate use of antibiotics. These include the appearance of antibacterial resistance, a situation declared by the WHO as a global public health problem. Aim: To describe the prescription of linezolid in a high complexity hospital in Bogotá, Colombia,considering the follow-up of the recommendations for the use of the drug included in clinical practice guidelines (CPG) and its indications. Methods: A descriptive observational study of longitudinal section was performed with retrospective collection of the information of all patients who were prescribed linezolid, at a minimum dose of 600 mg every 12 h during their hospitalization in the period from January 1st, 2017, to December 31st, 2018. The characteristics of linezolid prescription were described. Results: 133 prescriptions were reviewed. The most frequently diagnosed were sepsis of different origin (pulmonary abdominal, urinary) with 22.6 % (30/133), followed by skin and soft tissue infection 16.5 % (22/133), the pneumonia with 12.8 % (17/133) and urinary tract infections with 9.8 % (13/133). Two days treatment was the most frequent (range 1-30 days). In 33 % (44/133) of the patients, linezolid was used empirically (without using a previous antibiotic), while in 40.6 % (54/133) it was used as a second option (a previous antibiotic scheme). It was used as a third option in 20.3 % (27/133). Finally, in 6 % (8/133) of the patients, linezolid was prescribed after three previous antibiotics. It was necessary to use another antibiotic in near fifty percent of patients because linezolid did not work. Conclusions: The present study shows that there is little adherence to the institutional CPGs in relation to the treatment time, the microorganism identification, and the use as first option. The absence of a full-time infectious disease specialist, the high workload and the continuous rotation of prescribing staff may be the causeof these results. Some cases of inappropriate use may be related to the clinicalcondition of the patient which requires empirical treatments. Introducción: el estudio de la prescripción de antibióticos de última generación ayuda a identificar las causas y consecuencias del uso inadecuado de antibióticos. Estas incluyen la aparición de resistencia a los antibacterianos, situación declarada por la OMS como un problema de salud pública mundial. Objetivos: describir la prescripción de linezolid en un hospital de alta complejidad de Bogotá, Colombia, teniendo en cuenta el seguimiento de las recomendaciones de uso del fármaco incluidas en las guías de práctica clínica (GPC) y sus indicaciones. Métodos: se realizó un estudio observacional descriptivo de corte longitudinal con recolección retrospectiva de la información de todos los pacientes a los que se les prescribió linezolid, a una dosis mínima de 600 mg cada 12 h durante el período del 1 de enero de 2017 al 31 de diciembre de 2018. Se describieron las características de la prescripción de linezolid. Resultados: se revisaron 133 prescripciones. Los diagnósticos más frecuentes fueron la sepsis de diferente origen (pulmonar abdominal, urinaria) con el 22,6 % (30/133), seguida de la infección de piel y tejidos blandos con el 16,5 % (22/133), la neumonía con el 12,8 % (17/133) y las infecciones del tracto urinario con un 9,8 % (13/133). El tratamiento de dos días fue el más frecuente (rango 1-30 días). En el 33% (44/133) de los pacientes se utilizó linezolid de forma empírica (sin utilizar antibiótico previo), mientras que en el 40,6 (54/133) se utilizó como segunda opción (esquema antibiótico previo). Se utilizó como tercera opción en el 20,3 % (27/133). Finalmente, en el 6 % (8/133) de los pacientes se prescribió linezolid después de tres antibióticos previos. Fue necesario utilizar otro antibiótico en cerca del cincuenta por ciento de los pacientes porque linezolid no funcionó. Conclusiones: existe poca adherencia a las GPC institucionales en lo relacionado con el tiempo de tratamiento, la identificación del microorganismo, y la utilización como primera opción. La falta de un infectólogo de tiempo completo, la alta carga laboral y la continua rotación de personal prescriptor pueden ser las causas de estos resultados. Algunos casos de uso no adecuado pueden estar relacionados con la condición clínica del paciente que obliga a realizar tratamientos empíricos. Introdução: o estudo da prescrição de antibióticos de última geração auxilia na identificação das causas e consequências do uso inadequado de antibióticos. Entre eles está o surgimento de resistência aos antibacterianos, situação declarada pela OMS como um problema de saúde pública global. Objetivos: descrever a prescrição de linezolida em hospital de alta complexidade de Bogotá, na Colômbia, levando em consideração o acompanhamento das recomendações de uso de medicamentos constantes das diretrizes de prática clínica (CPG) e suas indicações. Métodos: foi realizado um estudo observacional transversal e descritivo com coleta retrospectiva de informações de todos os pacientes que receberam prescrição de linezolida, na dose mínima de 600 mg a cada 12 h durante o período de 1 de janeiro de 2017 a 31 de dezembro de 2018. As características de prescrição da...