Pneumocystis jirovecii following rituximab

Trends in the Epidemiology of Pneumocystis Pneumonia in Immunocompromised Patients without HIV Infection

The increasing morbidity and mortality of life-threatening Pneumocystis pneumonia (PCP) in immunocompromised people poses a global concern, prompting the World Health Organization to list it as one of the 19 priority invasive fungal diseases, calling for increased research and public health action. In response to this initiative, we provide this review on the epidemiology of PCP in non-HIV patients with various immunodeficient conditions, including the use of immunosuppressive agents, cancer therapies, solid organ and stem cell transplantation, autoimmune and inflammatory diseases, inherited or primary immunodeficiencies, and COVID-19. Special attention is given to the molecular epidemiology of PCP outbreaks in solid organ transplant recipients; the risk of PCP associated with the increasing use of immunodepleting monoclonal antibodies and a wide range of genetic defects causing primary immunodeficiency; the trend of concurrent infection of PCP in COVID-19; the prevalence of colonization; and the rising evidence supporting de novo infection rather than reactivation of latent infection in the pathogenesis of PCP. Additionally, we provide a concise discussion of the varying effects of different immunodeficient conditions on distinct components of the immune system. The objective of this review is to increase awareness and knowledge of PCP in non-HIV patients, thereby improving the early identification and treatment of patients susceptible to PCP.

Case Report: Successful treatment of severe pneumocystis carinii pneumonia in a case series of primary nephrotic syndrome after receiving anti-CD20 monoclonal antibody therapy

Rituximab is emerging as a new steroid sparing agent in children with difficult-to-treat nephrotic syndrome due to its ability of depleting CD20-positive B cells. Life-threatening adverse events such as pneumocystis carinii pneumonia may occur even though it seems to be well tolerated. Since rituximab is wildly used in immune-mediated diseases, it is important to manage its severe adverse events. To explore the importance of early diagnosis and treatment of pneumocystis carinii pneumonia in children with primary nephrotic syndrome (PNS) after receiving rituximab therapy, we retrospectively analyzed the clinical data of PNS patients younger than 18 years old with pneumocystis carinii pneumonia who were hospitalized in our center. Clinical features and laboratory test results were retrieved from the electronic medical records. Severe pneumocystis carinii pneumonia occurred in one child with steroid resistant nephrotic syndrome and two with steroid dependent nephrotic syndrome patients after rituximab treatment. These patients were diagnosed in time by metagenomic next-generation sequencing (mNGS) for pathogen detection. Fortunately, all three patients survived after antifungal treatment and achieved complete remission eventually. In conclusion, early diagnosis by using mNGS and timely antifungal treatment is the key to successful management of pneumocystis carinii pneumonia in children with difficult-to-treat PNS.