Source: JFMS Open Rep. 2020 Mar 13;6(1):2055116920909668. doi: 10.1177/2055116920909668.

 

A 2-year-old female neutered domestic shorthair cat presented with an 18-month history of intermittent lameness on all four limbs. The cat was markedly lame on all four limbs. Physical examination detected pain on palpation of the calcaneus bone and Achilles tendon bilaterally, and general resentment to handling. Investigations revealed an elevated creatine kinase, a positive Toxoplasma gondii IgG titre, toxic neutrophilic inflammation within the Achilles tendon bursae, electromyography and nerve conduction velocity studies consistent with a diffuse muscular disease, and histopathology of the muscle consistent with a chronic and diffuse myopathy. Arthrocentesis samples and an antinuclear antibodies titre were normal. Prior treatment with meloxicam had been ineffective. A 6-week course of clindamycin was prescribed; an improvement was seen within 3 days and clinical resolution at 3 months. The cat remained clinically normal after 20 months. This report suggests toxoplasmosis should be considered as a differential diagnosis in cats with myopathies or lameness in the absence of other causes.

Figure 1

Toe-walking on the left forelimb with hunched posture. (b) Weightbearing on the dorsal aspect of the left carpus. (c) Sitting back on the hindlimbs and non-weightbearing on the forelimbs

 

Figure 2

Neutrophil containing a duck egg blue cytoplasmic inclusion (far left) seen on cytology of Achilles tendon bursal fluid (suspected to be a lupus cell or Döhle body)