Adult alpaca case report highlights systemic toxoplasmosis

A newly published Journal of Veterinary Diagnostic Investigation case report describes fatal systemic toxoplasmosis in an adult alpaca, adding an unusual presentation to the limited camelid literature on clinical Toxoplasma gondii disease. The animal, an 11-year-old female alpaca, had a short history of sternal recumbency before death, and postmortem examination identified extensive thoracic, abdominal, pulmonary, hepatic, and adipose lesions consistent with disseminated disease. (deepdyve.com)

That matters because most of what veterinarians have seen in the published alpaca literature has centered on exposure, abortion, or younger animals, not fatal systemic disease in an older adult. Earlier reports have documented toxoplasmosis-associated abortion in an alpaca fetus, while a llama case report described acute fatal visceral disseminated lesions in a 13-month-old animal. Separately, serologic and isolation studies suggest that camelids encounter T. gondii more often than the sparse number of clinical case reports would imply. More broadly, alpaca medicine still has relatively thin species-specific diagnostic reference literature in some areas; for example, a cadaveric CT/MRI anatomy study noted that even normal nasal cavity and paranasal sinus anatomy has been underdescribed in alpacas, underscoring why case reports and foundational imaging studies can both carry outsized practical value in this species. (pubmed.ncbi.nlm.nih.gov)

In the new case, the gross findings included hydrothorax, ascites, hepatomegaly, fibrinous pleuritis, cranioventral bronchopneumonia, pulmonary atelectasis, and unusually firm adipose tissue in the thorax and abdomen. Microscopic lesions included chronic lymphocytic and histiocytic hepatitis with necrosis and portal-to-portal bridging fibrosis, thrombosis in thoracic and abdominal fat, and fibrinosuppurative inflammation, according to the abstracted report details. The article was published in January 2026, and the case had also appeared in the 2025 American College of Veterinary Pathologists scientific program, suggesting it drew attention in pathology circles before full publication. (deepdyve.com)

The broader epidemiology helps explain why this report is clinically relevant even if the presentation is rare. A systematic review and meta-analysis published in 2021 estimated pooled T. gondii seroprevalence in Camelidae at 28.16%, with variation by region. A U.S. study also isolated viable T. gondii from tissues of seropositive alpacas, reinforcing that infection is not merely theoretical in this species. Inference: the combination of frequent exposure and infrequent diagnosis of overt disease may mean some camelid infections go unrecognized unless necropsy, histopathology, and confirmatory testing are pursued aggressively. (pubmed.ncbi.nlm.nih.gov)

Direct expert reaction to this specific paper was not readily available in press materials or trade coverage I could verify, but the existing camelid and reference literature is directionally consistent. IVIS camelid reproduction resources note that abortion in llamas and alpacas has been associated with toxoplasmosis, while Merck Veterinary Manual materials describe toxoplasmosis as a systemic protozoal disease acquired through ingestion of environmentally shed oocysts or tissue cysts, with severe generalized disease more likely in susceptible hosts. Those sources don’t address this exact adult alpaca case, but they support the report’s significance as an uncommon manifestation of a familiar pathogen. A separate imaging anatomy study also helps illustrate the state of the field: in seven alpaca heads examined with CT and MRI, all had dorsal and middle conchal, maxillary, frontal, and ethmoidal sinuses; six had a sphenoidal sinus; five had bilateral lacrimal sinuses; and none had ventral conchal or palatine sinuses. The frontal sinus was typically split into a small medial compartment and a larger, variably concamerated lateral compartment, while ethmoidal air cells formed medial and lateral groups with different extensions and sinus connections. That kind of baseline anatomic detail is not directly about toxoplasmosis, but it strengthens the diagnostic toolkit available to clinicians and imagers working through uncommon alpaca disease presentations. (ivis.org)

Why it matters: For veterinarians, especially those in camelid, mixed, and diagnostic practice, this case expands the practical differential diagnosis for adult alpacas presenting with recumbency and multisystemic illness. It also underscores the value of postmortem workups when ante-mortem signs are nonspecific. Respiratory disease, abdominal effusion, hepatic pathology, and thrombotic or inflammatory adipose lesions may not immediately point clinicians toward toxoplasmosis in a camelid, but this report suggests they should at least consider it. The herd-level implications are also important: if cats have access to hay, feed storage, or pasture, discussions with pet parents about biosecurity and reproductive risk become more concrete. And at a species level, the case lands in a literature base that is still filling in normal-reference gaps, including cross-sectional head anatomy needed for confident CT/MRI interpretation in alpacas. (deepdyve.com)

What to watch: The next step is whether this case prompts more targeted reporting of adult camelid toxoplasmosis, including use of PCR, immunohistochemistry, and necropsy-based surveillance in unexplained deaths. If additional cases surface, clinicians may begin to see this not as an isolated pathology curiosity, but as a rare diagnosis that’s probably underdetected. In parallel, more alpaca-specific reference work—like the recent CT/MRI and 3D volume-rendering description of normal nasal cavity and sinus anatomy—could improve confidence in imaging interpretation and help clinicians distinguish unusual pathology from normal species variation. (acvp.org)