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Infectious Disease

Sarcocystis

Sarcocystosis is an infection caused by the intracellular protozoan parasites of the Sarcocystis species, with a global distribution but sporadic occurrence in humans. Most human infections are asymptomatic and typically discovered incidentally, making it a relatively rare condition. The parasite can be contracted by consuming undercooked meat or contaminated food and water. When symptomatic, sarcocystosis may present with gastrointestinal or muscular symptoms. Due to the challenges in diagnosin

v1 · Reviewed Nov 7, 2026 by Automated Clinical Reviewer (Strict Verbatim v1)
  • Muscular sarcocystosis can present with fever, musculoskeletal pain, rashes, bronchospasms, cardiomyopathy, or subcutaneous swelling.
  • Occasionally, there can be a disseminated disease that can cause significant morbidity.
  • Some cases of muscular sarcocystosis can develop into severe myositis.
  • Very rarely, there can be a disseminated disease that can affect multiple organs.
  • Screen patients with potential exposure to contaminated food or undercooked meat for sarcocystosis.
  • Implement appropriate diagnostic tests, such as serology and muscle biopsy, for confirming sarcocystosis.
  • Blood investigations can show lymphocytosis or eosinophilia.
  • In muscular disease, elevated creatine kinase or lactate dehydrogenase may be seen.
  • Fecal studies can include different flotation techniques, modified Kato thick smear, formalin-ether technique, or direct smear.
  • Muscle biopsy light microscopy can show the sarcocyst in muscular sarcocystosis, which may or may not show bradyzoites.
  • Imaging, including magnetic resonance imaging, may help detect muscle cysts and direct biopsies.
  • Immunofluorescence assays, enzyme-linked immunosorbent assays, and serological methods such as antibodies to Sarcocystis have been tried but are not widely available.
  • There are no effective prophylaxis or therapeutic options for intestinal sarcocystosis in either humans or animals.
  • The role of cotrimoxazole remains unclear as there have been reports of improvement in symptoms and the absence of elevation of creatine kinase levels.
  • Corticosteroids were demonstrated to ameliorate myositis.
Corticosteroids
Not specified in source
Adult
Not specified in source
Renal
Not specified in source
Duration
Not specified in source
  • Dithiazanine was tested in a patient, but Sarcocystis persisted.
  • Pyrimethamine with sulfisoxazole was also not effective.
  • Acetylspiramycin did not show adequate response either.
  • In some instances, there have been reports of resection surgery of the affected ileum.
  • Albendazole therapy was trialed with steroid cover for muscular sarcocystosis, which was ineffective.
  • In vitro study results have demonstrated that pyrimethamine and trimethoprim demonstrated activity against Sarcocystis , but no well-conducted clinical studies have been conducted.
  • Segmental eosinophilic enteritis or necrotizing enteritis may be seen in intestinal sarcocystosis.
  • Some cases of muscular sarcocystosis can develop into severe myositis.
  • Very rarely, there can be a disseminated disease that can affect multiple organs.
  • In muscular disease, elevated creatine kinase or lactate dehydrogenase may be seen.
  • The physical examination can show lymphadenopathy, hepatomegaly, or tender muscles in case of disseminated disease or may be expected in localized muscular or intestinal disease.
  • review
    Sarcocystis. StatPearls [Internet] — Balram Rathish, Raksha K — StatPearls Publishing, 2022

Decision support only. Verify against local protocols and current labeling. Source: www.ncbi.nlm.nih.gov