Stiff Leg Syndrome and Myelitis with Anti-Amphiphysin Antibodies: A Common Physiopathology

culty in walking. The symptoms had first appeared 2 weeks earlier. Her medical history included type 2 diabetes treated with metformin and a thyroid goiter treated with surgery and levothyroxine. On clinical examination, she presented permanent hypertonia in the lower limb and bilateral dystonia of the extensor hallucis longus muscles. Intermittent spasms were associated with hypertonia. The spasms lasted several seconds and were spontaneous, painful, and made worse by anxiety and cutaneous stimulation. The tibialis anterior muscles were hypertrophied. Electroneuromyography (ENMG) carried out under diazepam was normal. Cerebral and medullary MRI ( fig. 1 ) were normal. A PET scan showed an anomaly on the right breast. A mammography, breast ultrasound and biopsy confirmed the diagnosis of infiltrating canal carcinoma of the breast. The standard biological assessment was normal. Cerebrospinal fluid (CSF) tests showed pleocytosis (14 white blood cells), a high protein level (0.81 g/l) and intrathecal IgG synthesis with monoclon al bands. Other biological examinations were done: Lyme disease, HTLV (1 and 2) and tetanus serology were negative. Tests for antiphospholipid, antinuclear and anti-GAD antibodies were negative. No antiDear Sir, Stiff man syndrome is a rare neurological pathology first described in 1956 by Moersch and Woltman [1] . Four forms of the illness have been identified: stiff person syndrome, which is characterized by contractions and axial muscle rigidity; progressive encephalomyelitis with rigidity, characterized by diffuse rigidity and cognitive disorders; jerking stiff man syndrome, characterized by limb myoclonus and respiratory disorders; and stiff leg syndrome (SLS), which is characterized by focal rigidity and is different in various ways [2] . Anti-GAD antibodies are positive in only 15% of cases of SLS. Contractions and rigidity affect only one or two limbs. A paraneoplastic etiology is rarely associated with it. Medullary and cerebral MRI do not usually show any abnormalities [3] . We report the case of a patient suffering from SLS with anti-amphiphysin antibodies revealing breast cancer, with paraneoplastic transverse myelitis (TM) images appearing later in MRI with no as sociated neurological deficit.