Decades of numerous large-scale and singular case studies, providing science-based evidence implicating toxoplasma gondii in both polymyositis and dermatomyositis in adult and pediatric populations.
[Juvenile dermatomyositis and toxoplasmosis: a rare association]. Acta Reumatol Port. 2009 Jul-Sep;34(3):546-50.
A case study, describing infection with toxoplasmosis in a 13-year-old female with dermatomyositis. In spite of treatment with corticosteroids and immune-suppressants, the child did not improve until appropriate parasitic treatment was initiated.
Dermatomyositis-like syndrome following acute toxoplasmosis. Bull Soc Sci Med Grand Duche Luxemb. 2004;(2):109-19.
The case of a patient who developed an acute “dermatomyositis-like” syndrome after infection by the protozoan parasite, toxoplasma gondii, is described.
[Toxoplasmosis and dermatomyositis: a causal or casual relationship?]. Pediatr Med Chir. 1989 Mar-Apr;11(2):197-203.
A case of toxoplasmosis in a 10-year-old female with positive serology and exhibiting the typical clinical picture for dermatomyositis is described. Study authors suggest that patients with polymyositis/dermatomyositis are tested for toxoplasmosis, particularly when steroids and immune-suppressants are being considered, as appropriate anti-protozoal therapy produces clinical benefit.
Juvenile dermatomyositis induced by toxoplasmosis. J Child Neurol. 1987 Apr;2(2):101-4.
Case study of a 10-year-old female, who had close contact with cats, developed all the classic features of dermatomyositis that was confirmed by muscle biopsy. Serological testing revealed elevated toxoplasma gondii titers, but she experienced rapid improvement with 4 weeks of combination antibiotics and steroids, after which all clinical signs and symptoms resolved. A year later, only mild impairment of natural killer cells and ANA remained positive, but all other lab markers had normalized, including lymphocytic response to T-cell and B-cell mitogens, immunoglobulin and complement levels.
In a study of 58 dermatomyositis/polymyositis patients at two medical centers, testing was conducted to look for evidence of toxoplasma gondii infection using different testing methods – serum testing of IgM antibodies using a specific indirect immunofluorescent technique, the Sabin-Feldman dye test, and complement fixation methods. Results showed that 50% of patients were positive on the Sabin-Feldman dye test, yet only 24% were positive on indirect immunofluorescent testing. Interestingly, where the Sabin-Feldman dye test was negative, the IgM immunofluorescent antibodies were also negative. However, in those who tested positive for IgM immunofluorescent antibodies, these patients also tested positive on both the Sabin-Feldman dye test and complement fixation antibody test. The authors also provide evidence that neither a positive antinuclear antibody or rheumatoid factor test had any influence on these results.
Dermatomyositis responding to treatment of associated toxoplasmosis. Br J Dermatol. 1991 Jul;125(1):76-8.
Case of a 59-year-old woman with severe dermatomyositis and a diagnosis of serologically-confirmed toxoplasmosis, supporting an etiopathogenetic role for this parasitic infection.
[Systemic lupus erythematosus, polymyositis and toxoplasma antibodies]. Sem Hop. 1983 Jan 6;59(1):43-6.
A case of polymyositis with an overlap of lupus is discussed, in which high toxoplasma gondii IgG (past infection) antibodies were evident, but muscle biopsy by immunofluorescence and injection of muscle extracts into mice failed to produce evidence of the infection. Study authors discuss the aggressive nature of toxoplasma gondii and its ability to revert to dormant cysts, but with the capability to reactivate later when immunologic function is compromised and, in this case, a complement deficiency due to lupus.
Toxoplasmic myocarditis and polymyositis in patients with acute acquired toxoplasmosis diagnosed during life. Clin Infect Dis. 1997 Apr;24(4):676-83.
First case biopsy-proven report of a woman with toxoplasmic-induced polymyositis with myocarditis and chorioretinitis, confirmed by positive serology, and treated successfully for the infection. Study authors state that because such cases have only been solved, after death by post-mortem testing, that any patient presenting with polymyositis and myocarditis of unknown origin, should be tested for toxoplasma gondii and that both PCR testing and endomyocardial or skeletal muscle tissue biopsies can confirm the diagnosis.
Polyomyositis and myocarditis associated with acquired toxoplasmosis in an immunocompetent girl. BMC Musculoskelet Disord 2: 8. doi: 10.1186/1471-2474-2-8
Serologic confirmation of both IgM and IgG antibody testing for toxoplasmosis was made in a 13-year-old girl presenting with polymyositis and myocarditis. Prior to diagnosis, the child’s medical team suspected liver abscess and treated with antibiotics accordingly, but the child worsened significantly. Fearing organ damage, the child was then treated with intravenous prednisolone, captopril, digoxin and naproxen was added later. All drugs administered were tapered over a 12-month period at which time toxoplasma gondii IgG antibodies (past infection) remained highly elevated. At 18 months, the child was free of symptoms and IgG antibodies also began to decrease. At four-year follow-up, the child was free of symptoms and clinical findings. The authors state that acute myopathies in children are usually associated with infection, such as Staphylococci, Mycoplasmas, Coxsackie group B and influenza viruses, trichinosis, toxoplasmosis, and cysticercosis and that all such cases should be investigated for the infectious cause of acute myopathy.
Increased toxoplasma antibodies in idiopathic inflammatory muscle disease. A case-controlled study. Arthritis Rheum. 1979 Mar;22(3):209-14
In a case-controlled study (1979) of 69 polymyositis/dermatomyositis/myositis-related to other connective tissue disease patients, toxoplasma gondii antibody testing was conducted. Findings revealed that complement fixation toxoplasma antibodies, correlated with high IgM levels, were significantly more frequent in polymyositis and that this data indicates recent infection with toxoplasma gondii in these patients.
Toxoplasmic polymyositis revisited: case report and review of literature. Neuromuscul Disord. 1997 Sep;7(6-7):390-6.
In the Journal of Neuromuscular Disorders (1997), case study authors present the case of polymyositis in a heart transplant patient with biopsy-proven toxoplasma gondii infection. The patient recovered with anti-protozoal therapy in combination with plasmapheresis. These authors make the case for toxoplasmic-induced polymyositis by either recent infection or reactivated latent infection and that all cases of polymyositis should be evaluated for the infection and that a trial of anti-protozoal therapy be administered, if indicated.
Acute acquired toxoplasmosis presenting as polymyositis and chorioretinitis in immunocompetent patient. Joint Bone Spine. 2008 Oct;75(5):603-5. doi: 10.1016/j.jbspin.2007.08.009. Epub 2008 Apr 10.
In the discussion of a case of acute onset polymyositis with chorioretinitis in an immunocompetent patient due to toxoplasmosis infection, study authors state that it has been previously established that this protozoan infection can cause myositis, either by newly-acquired infection or by reactivation of latent infection. Authors also recommend that all patients presenting with polymyositis should be tested for the infection during initial evaluation and, if serology is positive, that anti-protozoal treatment should be initiated.
Acquired cutaneous toxoplasmosis. Dermatologica. 1983;167(1):24-32.
The development of polymyositis in a patient with toxoplasmosis: clinical and pathologic findings and review of literature. Clin Exp Rheumatol. 1984 Jul-Sep;2(3):205-8.
The case of a 58-year-old woman is described, presenting with fever, rash, myalgia, muscle weakness and cervical lymphadenopathy, confirmed to have toxoplasmosis by lymph node biopsy and elevated IgM and IgG toxoplasma gondii antibody titers. After a two-month course of prednisone, along with sulfadiazine and pyrimethamine, the patient improved in the subsequent four months. In the 4.5 years that followed, her toxoplasma antibody titers decreased, but she went on to develop polymyositis.
Polymyositis and toxoplasmosis. Acta Pathol Jpn. 1981 Jul;31(4):675-80.
Study authors recommend a serological and histopathological search for toxoplasmic infection in every case of polymyositis to further elucidate upon the relationship of this infection with polymyositis and to ensure appropriate therapy. This recommendation follows the presentation of a case of polymyositis where toxoplasma gondii was confirmed by positive serology, muscle and liver biopsy.
Dermatomyositis-like syndrome due to toxoplasma. Br J Dermatol. 1979 Nov;101(5):589-91.
A woman presented with seronegative dermatomyositis, but with classic observable signs and symptoms of the disease. She was serologically positive for toxoplasma gondii and muscle tissue, transferred to mice, was cultured and also tested positive for the infection. After appropriate treatment with pyrimethamine and sulphametoxypyridine, improvement was noted, further confirming the diagnosis of toxoplasmic-induced dermatomyositis.
Toxoplasmosis appearing to be dermatomyositis. Arch Dermatol. 1979 Jun;115(6):736-7.
Following the successful and dramatic resolution of dermatomyositis within 2 weeks in a boy presenting simultaneously with toxoplasmosis, after treatment with sulfadiazine and pyrimethamine, the case study authors recommend toxoplasma gondii investigation in all dermatomyositis and polymyositis patients. They further state that treatment with sulfadiazine, pyrimethamine, and folinic acid may be a valuable alternative to immune-suppressants and steroids.
Adult toxoplasmosis presenting as polymyositis and cerebellar ataxia. Ann Intern Med. 1975 Mar;82(3):367-71.
This case study describes a patient with positive serology and muscle biopsy findings for Toxoplasma gondi infection who presented with polymyositis and cerebellar ataxia. Additional findings included spinal cord, nerve root involvement and musculoskeletal symptoms. Recurrent disease was observed over a 3-year period with limited, temporary response to “specific” treatment and persistently elevated toxoplasma antibody titers.
Toxoplasmic myositis as a presenting manifestation of idiopathic CD4 lymphocytopenia. Muscle Nerve. 2003 Jun;27(6):761-5.
The case of a muscle biopsy-proven case of toxoplasmic myositis in a patient and CD4 lymphocytopenia, which is considered rare and usually associated with opportunistic infections. The patient recovered by being administered a combination of antiprotozoal therapy and steroids. The authors point out that Toxoplasma gondii can encyst in muscle tissue.
Further relevant studies for which study abstracts are unavailable, but that may be accessible with subscription to the associated journal.
[Elevated toxoplasma antibody titers in a patient with dermatomyositis]. Nihon Naika Gakkai Zasshi. 1985 Aug;74(8):1098-102.
[A case of dermatomyositis associated with toxoplasmosis].Nihon Naika Gakkai Zasshi. 1986 May;75(5):633-7.
Serologic evidence of toxoplasmosis among patients with polymyositis. Am J Med. 1974 Feb;56(2):186-91. Later studies (1983) demonstrated that more comprehensive testing methods for toxoplasma gondii may be helpful in revealing this infection.