A Rare Sequela of Untreated Streptococcus Pharyngitis: A Case Report.

Pharyngitis is commonly caused by the gram positive bacteria, streptococcus. Given the potential morbid complications of untreated streptococcal pharyngitis, antibiotics are critical. One of the rarer complications is pulmonary-renal syndrome (PRS), defined as rapidly progressive glomerulonephritis and diffuse alveolar hemorrhage. PRS is associated with high rates of morbidity and mortality, making swift diagnosis and treatment imperative for survival. More common causes of PRS are tied to autoimmune diseases. This case describes a novel progression of PRS caused by streptococcus. A 26-year-old male with no significant medical history presented to our emergency department with streptococcal group A-positive sore throat. After discontinuing amoxicillin due to pruritus, the patient returned one month later with persisting hematuria and dysuria, diagnosed with post-streptococcal glomerulonephritis. Despite receiving another antibiotic prescription, it was not filled. He returned six days later with worsening symptoms, leading to ICU admission due to hemoptysis requiring subsequent intubation. Diffuse alveolar hemorrhage was confirmed with bronchial washings. Negative autoimmune laboratory results and clinical symptoms suggest streptococcal pharyngitis induced pulmonary-renal syndrome. Although only the sixth case of streptococcal induced PRS, it is imperative to consider when treating patients with diffuse alveolar hemorrhage, due to its possible mortality. Prompt recognition and treatment with pulse steroids and plasmapheresis is crucial for PRS resolution. Laryngoscope, 2025.