B48.5: Pneumocystosis

Pneumocystosis, described under the ICD-10 code B48.5, is a type of fungal infection that predominantly affects the lungs, leading to a condition known as Pneumocystis pneumonia. This disease is caused by a fungus known as Pneumocystis jirovecii. People with healthy immune systems can carry this fungus without it causing any disease. However, individuals with weakened immune systems, such as those with HIV/AIDS, individuals on chemotherapy, or organ transplant recipients, are more likely to develop symptomatic Pneumocystis pneumonia. Common symptoms include fever, non-productive cough, shortness of breath, and fatigue. If not treated, this can progress to cause severe difficulty breathing and can even be life-threatening. The fungus spreads through the air, meaning you can get it by inhaling fungal spores.