Images in Pathology - Leptospirosis Associated With Diffuse Alveolar Haemorrhage

A 48-year-old man presented with high grade fever with chills, cough with mucoid expectoration, occasional streaky haemoptysis, bilateral lower chest pain, progressive exertional breathlessness and oliguria of two days' duration. He also had haematemesis and malena one day prior to admission. Physical examination on admission revealed a feeble pulse, hypotension, tachypnoea, icterus, pallor and subconjunctival suffusion. Bilateral coarse crepitations were heard on examination of the respiratory system. He also had a mild hepatomegaly and altered sensorium. Investigations revealed haemoglobin concentration of 8.5 gm% and a total leucocyte count of 37,300/cmm with 92% neutrophils and 18% lymphocytes. His blood urea nitrogen was 200 mg%, serum creatinine 4.5 mg%, total bilirubin 23.0 mg%, direct bilirubin 16.0 mg%, serum alanine aminotransferase 1100 I.U./ml, serum aspartate aminotransferase 1072 I.U./ml. The prothrombin time and activated partial thromboplastin time were prolonged. The analysis of arterial blood gases revealed severe hypoxia with metabolic acidosis. Smears for malarial parasites and tests for human immunodeficiency virus and hepatitis B surface antigen were negative. Chest radiographs revealed bilateral diffuse ill-defined shadows. The microscopic agglutination test for leptospirosis was positive. The patient died within half an hour of admission. A complete autopsy was performed. External examination revealed an averagely built and nourished individual with icterus, pallor and subconjunctival suffusion. On gross examination the lungs were firm, plum coloured with pleural petechial haemorrh-ages. Other salient macroscopic findings were epicardial petechiae, a mildly enlarged, soft and yellow liver, swollen and congested kidneys and serosanguinous gastric contents. Histological sections of the kidneys revealed a mild diffuse interstitial lymphocytic infiltrate forming focal aggregates at places, accompanied with cloudy change of the tubules and focal tubular necrosis (Figure 1). The most severe lesions were seen in the lungs. They showed that majority of the alveoli and airways were filled with haemorrhage (Figure 2). Sections of the liver showed focal necrosis and a mononuclear portal inflammation while the brain revealed ischemic changes in the neurons. Levaditi's stain on the kidney sections showed numerous blackish, tiny curved rods resembling leptospira (Figure 3). Immunohistochemisty for leptospira performed on the kidney sections confirmed the diagnosis of leptospirosis (Figure 4).

Keywords
Osteochondroma, chondroblastoma, chondral tumours, cartilage germ cells