Adult patients with idiopathic pulmonary hemosiderosis: a comprehensive review of the literature.

Idiopathic pulmonary hemosiderosis (IPH) is a rare disease without a known incidence or prevalence in adults. Our knowledge of this entity is limited as there is no prospective or retrospective study with a reasonable number of patients. The objective is to describe the demographics, clinical manifestations, diagnosis, treatment, and prognosis of adult patients with IPH. The Medline and Embase databases were searched from inception to 2021 with appropriate search formulas to identify relevant articles following strict inclusion and exclusion criteria. Statistical analyses were performed for the entire cohort and prespecified subgroups. A total of 84 patients were identified. The majority of patients were males 54/84 (64.3%). The median age was 27 years. The manifesting symptoms were present in the following frequencies: anemia 76/83 (91.6%), dyspnea 71/83 (85.5%), hemoptysis 70/84 (83.3%), cough 22/84 (26.2%), and chest pain 9/84 (10.7%). The classic triad was present in 61/84 (79%) patients. The mean hemoglobin during the initial presentation was 8.4 gm/dL. A total of 16/57 (19.5%) tested positive for autoantibodies. The median delay in the diagnosis of IPH was 1.02 years. Immunosuppressive therapy was prescribed in 49/79 (62%) patients, and recurrence occurred in more than half of the patients 36/66 (54.5%). A total of 63/79 (79.7%) patients were alive during the final follow-up. IPH is more common in young adults with a male predominance. A high index of suspicion is necessary to attain an early diagnosis and possibly reduce the short-term mortality of nearly 20% and long-term complications.