While the advent of combination antiretroviral therapy (ART) has significantly improved survival, tuberculosis (TB) remains the leading cause of death in the HIV-infected population. We used Mycobacterium tuberculosis/simian immunodeficiency virus-coinfected (M. tuberculosis/SIV-coinfected) macaques to model M. tuberculosis/HIV coinfection and study the impact of ART on TB reactivation due to HIV infection. Although ART significantly reduced viral loads and increased CD4 + T cell counts in blood and bronchoalveolar lavage (BAL) samples, it did not reduce the relative risk of SIV-induced TB reactivation in ART-treated macaques in the early phase of treatment. CD4 + T cells were poorly restored specifically in the lung interstitium, despite their significant restoration in the alveolar compartment of the lung as well as in the periphery. IDO1 induction in myeloid cells in the inducible bronchus-associated lymphoid tissue (iBALT) likely contributed to dysregulated T cell homing and impaired lung immunity. Thus, although ART was indispensable for controlling viral replication, restoring CD4 + T cells, and preventing opportunistic infection, it appeared inadequate in reversing the clinical signs of TB reactivation during the relatively short duration of ART administered in this study. This finding warrants the modeling of concurrent treatment of TB and HIV to potentially reduce the risk of reactivation of TB due to HIV to inform treatment strategies in patients with M. tuberculosis/HIV coinfection.

Background Air sacculitis is an important clinical condition in non-human primates. Methods We evaluated 37 baboons and 7 chimpanzees with spontaneous air sacculitis submitted to pathology over a 20 year period. Results Air sacculitis was observed almost exclusively in males. Common reported signs were halitosis, coughing, nasal discharges, depression, anorexia, and weight loss. Gross lesions included thickened air sacs and suppurative exudate lining the walls. Microscopic lesions included marked epithelial hyperplasia or hypertrophy, necrosis, fibrosis, cellular infiltrates, and bacterial colonies. Mixed bacterial infections were more common than infections by single species of bacteria. Streptococcus sp. was the most frequent bacteria isolated in both baboons and chimpanzees. Conclusions This is the first report describing the gross and microscopic lesions of air sacculitis in chimpanzees. The preponderance of males suggests a male sex predilection in baboons.

Chimpanzees (Pan troglodytes) have served as an important model for studies of reproductive diseases and aging-related disorders in humans. However, limited information is available about spontaneously occurring reproductive tract lesions in aging chimpanzees. In this article, the authors present histopathologic descriptions of lesions identified in the reproductive tract, including the mammary gland, of 33 female and 34 male aged chimpanzees from 3 captive populations. The most common findings in female chimpanzees were ovarian atrophy, uterine leiomyoma, adenomyosis, and endometrial atrophy. The most common findings in male chimpanzees were seminiferous tubule degeneration and lymphocytic infiltrates in the prostate gland. Other less common lesions included an ovarian granulosa cell tumor, cystic endometrial hyperplasia, an endometrial polyp, uterine artery hypertrophy and mineralization, atrophic vaginitis, mammary gland inflammation, prostatic epithelial hyperplasia, dilated seminal vesicles, a sperm granuloma, and lymphocytic infiltrates in the epididymis. The findings in this study closely mimic changes described in the reproductive tract of aged humans, with the exception of a lack of malignant changes observed in the mammary gland and prostate gland.

Background We present the spontaneous causes of mortality for 137 chimpanzees (Pan troglodytes) over a 35 year period. Methods A records review of the pathology database was performed and a primary cause of mortality was determined for each chimpanzee. Results The most common causes of mortality were: cardiomyopathy (40% of all mortalities); stillbirth/abortion; acute myocardial necrosis; chimpanzee-induced trauma; amyloidosis; and pneumonia. Five morphologic diagnoses accounted for 61% of mortalities: cardiomyopathy; hemorrhage; acute myocardial necrosis; amyloidosis; and pneumonia. The most common etiologies were degenerative, undetermined, bacterial, traumatic, and neoplastic. The cardiovascular system was most frequently involved, followed by the gastrointestinal, respiratory, and multi-systemic diseases. Conclusions Degenerative diseases were the primary etiological cause of mortality of the adult captive chimpanzee population. Chimpanzee-induced trauma was the major etiological cause of mortality among the perinatal and infant population. This information should be a useful resource for veterinarians and researchers working with chimpanzees.