A 21-year-old Romanian man presented to our clinic for leanness assessment evolving for several years. He had been adopted at the age of 3 years old; hence, no familial history was available. His medical history was notable for dyspraxia, dyslexia, bilateral cryptorchidism, and scoliosis in infancy. He practiced water polo, swimming, and martial arts, but in recent years, amyotrophy and weakness of both arms had developed (Figure, A) without dyspnea or swallowing troubles. In searching for underlying disease, malabsorption, endocrinopathy, infections, cancer, and anorexia nervosa had been ruled out previously by many specialists. On physical examination the patient was healthy, with a body mass index of 17.5 kg/m2. Physical examination showed distal wasting of the deltoid muscle with a normal proximal part, wasting of the humeral muscle, and bilateral scapular winging (Figure, A, B) highly suggestive of facioscapulohumeral muscular dystrophy (FSHD). Muscle testing revealed bilateral weakness of deltoid and biceps muscles (4/5 Medical Research Council scale), as well as abdominal muscles and hip abductors on both sides. Orbicular muscles (eyes and lips) were also weak. No gait disturbance was noted. Routine blood examination was unremarkable, but the serum creatine phosphokinase level was 559 UI (<195 UI), with negative dot myositis. Electroneuromyography showed normal nerve conduction study and asymmetric myopathic features, predominately in the facial and scapulohumeral muscles. Mild diaphragmatic insufficiency was diagnosed (vital capacity 77%). Genetic testing confirmed FSHD type 1. D4Z4 contraction using Southern blot showed loss of microsatellite repeated units in the subtelomeric region of chromosome.
We report here a patient with typical clinical features of FSHD in whom the diagnosis was established late. Indeed, this disease is one of the most common muscular dystrophies in adults with autosomal dominant inheritance. Clinical features include weakness of the facial muscles and shoulder girdle musculature, resulting in scapular winging with an asymmetric muscle involvement, but also the trunk and legs, and a positive family history1, 2, 3 There is no cardiac involvement, but respiratory muscles may be affected.
Electroneuromyography features and biopsy are often nonspecific.2 Two genetic forms of FSHD were described: around 90% to 95% of patients have FSHD type 1, other patients have FSHD type 2. Patients with FSHD1 have a loss of D4Z4 macrosatellite repeated unit in the subtelomeric region of the long arm of chromosome 4q 2. Patients with FSHD2 have a mutation in the SMCHD1 gene (chromosome 18). Consensus criteria suggest screening for D4Z4 contraction using Southern blot in patients with characteristic clinical presentation.3
To date, there is no specific treatment for FSHD, and only supportive care is proposed, with muscle stretching and exercise, and assessing pulmonary and cardiac function with a baseline eye examination.3 Some authors suggest that scapular fixation can improve shoulder function.4 As FSHD1 is a genetic disorder, use of antisense oligonucleotide therapy to target DUX4 was proposed for FSHD but not actually tested on humans.5
Physicians should be aware of subtle signs and symptoms of FSDH in order to allow an early diagnosis (confirmed on genetic testing) and appropriate management without needing multiple diagnostic procedures.
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-Rim Bourguiba, MD, Marion Masingue, MD, Pierre-Jean Marc, MD, Thimothée Lenglet, MD, Claude Bachmeyer, MD
