Pablo's necropsy

Final Diagnosis
Fibrino-suppurative pleurisy, severe, acute: Streptococcus
Portal and periportal hepatitis, lymphoplasmocyte, moderate, chronic
Abdominal, fibrous adhesions, multifocal, extensive
Degeneration, atrophy and fibrosis of the right testicle, pronounced
Macroscopic examination

The subject is an adult, intact male chimpanzee weighing 78 kg without apparent marks of identification. Incisions on the abdominal and thoracic wall are present on the median ventral line (beginning of an autopsy by the owner). The subcutaneous tissue and viscera contain moderately abundant fat reserves. The muscular masses are well developed.

In the abdomen we noted extensive multifocal, fibrous adhesions that involved practically all of the viscera, the omentum and the abdominal wall.

The liver is large (2.3 kg) with moderately rounded edges and a very firm parenchyma of an orange marble colour with some redder zones. The gastro-intestinal tract showed signs of moderately advanced autolytic changes.

The thorax contained fibrinous material in abundant quantities in the two pleural cavities that adhered in a reductible way to the visceral and costal pleura . It also contained a moderate sero-fibrinous effusion .

The lungs showed extensive zones of congestion of the parenchyma without apparent consolidation.

The right testicle was reduced in volume and had a heterogeneous parenchyma with extensive fibrosis .

Microscopic examination

Lung: On the pleura there was a thick coating of fibrinous material that formed a network of thick rows and contained an abundant infiltration of neutrophils and macrophages in fewer numbers. A Gram staining revealed occasional extra-cellular gram-positive cocci that formed diplococci or short chains.

In the pulmonary parenchyma, we noted a general congestion of the alveolar capillaries with multifocal sites of intra-alveolar hemorrhaging. In some areas, there was an accumulation of macrophages, sometimes "bi- or oligo-nucleotides" in the alveoli . Many vessels were surrounded by "manchons de lymphoplasmocytaires". The epithelium of the bronchi was generally missing (autolysis), but we noted an infiltration of the chorion of the bronchial mucous membrane by abundant lymphocytes and plasmocytes, which also often infiltrated the mucosal glands as well as in some areas granulocytes .

Liver: In the majority of portals there was fibrosis and a light "lymphoplasmocytaire" infiltration which in certain areas infiltrated the "plaque limitante". In these areas, there was a disorganization of the hepatocellular rows with a proliferation of mesenchymal cells and a deposition of fine fibrillin of collagen. The portal hepatocells often had large nuclei a little pleomorphic with a chromatin "tres marginee" and a clear center of pale basophils (probable cytoplasmic invagination). Other hepatocytes were bi-nucleous. Rare, necrotic hepatocytes were noted in these zones.

Right testicle: Extensive zones of interstitial fibrosis of the testicular parenchyma were present. There was also the presence of hyalin and a complete absence of cells in the tubules . Very little of the normal seminiferous tissue remained.

Bacteriology

Streptococcus of the mitis group in the thoracic fibre (?) and in the lung.
Liver: negative

Commentary

The cause of death was an acute pleurisy due to a streptococcal infection. We also noted a hepatitis with an appearance that suggested a viral infection (possibly Hepatitis C). Tissue was sent to a federal laboratory to attempt to determine the virus type. The abdominal adhesions were probably the consequence of an old peritonitis. The cause of the atrophy and fibrosis of the testicle is uncertain; it could be due to a chronic hypoperfusion (partial blockage of the circulation due to the abdominal adhesions).