Approach to the immunocompromised patient with pulmonary nodules

The Challenge of Diagnosing Invasive Pulmonary Aspergillosis in Children: A Review of Existing and Emerging Tools

Invasive pulmonary aspergillosis remains a major cause of morbidity and mortality for immunocompromised children, particularly for patients with acute leukaemia and those undergoing haematopoietic stem cell transplantation. Timely diagnosis, using a combination of computed tomography (CT) imaging and microbiological testing, is key to improve prognosis, yet there are inherent challenges in this process. For CT imaging, changes in children are generally less specific than those reported in adults and recent data are limited. Respiratory sampling by either bronchoalveolar lavage or lung biopsy is recommended but is not always feasible in children, and serum biomarkers, including galactomannan, have important limitations. In this review we summarise the current paediatric data on available diagnostic tests for IPA and highlight key emerging diagnostic modalities with potential for future use.

Cytomegalovirus Cavitary Pneumonia in Nontransplant Pediatric Acute Lymphoblastic Leukemia: Case Report and Review of the Literature

Lung cavitary lesions are a rare finding in the nontransplant setting of a patient with acute leukemia. Among viral agents, cytomegalovirus (CMV) may cause pulmonary nodules and cavities in patients undergoing hematopoietic stem cell transplantation, but during pediatric acute lymphoblastic leukemia treatment, CMV disease is less common. Here we report the case of a boy affected by acute lymphoblastic leukemia who suffered severe cavitary CMV pneumonia during chemotherapy, and we review the current literature.

Legionella micdadei: A Forgotten Etiology of Growing Cavitary Nodules: A Case Report and Literature Review

Background. Legionella micdadei is a Gram negative bacterium that can stain weakly acid fast. It was first described in 1979 after immunosuppressed patients developed pneumonia at a Pittsburgh VA, initially given the name Pittsburgh Pneumonia Agent. It is the second most common Legionella species causing infection after pneumophila, and typically infects immunocompromised hosts. It is not easy to be cultured which makes diagnosing difficult. Case Presentation. A 31-year-old female with ulcerative colitis, primary sclerosing cholangitis, and cirrhosis presented with fever, chills, shortness of breath, dry cough, and chest pain for five days after being started on immunosuppression for autoimmune hepatitis two months earlier. The first chest CT showed small bilateral cavitary nodules. The nodules continued to grow on subsequent imaging despite what was thought to be appropriate therapy. A transthoracic biopsy was performed which grew Legionella micdadei and the patient improved after being treated with levofloxacin. Conclusion. Legionella micdadei is an atypical pathogen known to cause pneumonia in immunosuppressed patients. This case highlights a typical presentation of an atypical infection not commonly thought about and should be considered when nodules are growing despite being on broad antimicrobial therapy.