Fig. 8

Limb Girdle Muscular Dystrophy R1, LGMD R1, calpainopathy, muscle imaging, Western blot and muscle biopsy light and electron microscopy findings of a 36 years old male patient with two heterozygous variants in the CAPN3 gene c.865 C > T: p.(Arg289Trp) probably pathogenic and c.619_620delinsGc:p.(Lys207Ala) of uncertain pathogenicity and proof of pathogenicity with muscle biopsy Western blot. a, b, and c. T1-weighted axial Magnetic resonance imaging of the pelvis (a), thighs (b), and legs (c). a. Pelvis with severe muscle fat replacement of gluteus maximus, gluteus medius, and gluteus minimus. b Thighs with muscle fat replacement of adductor magnus (red asterisk * in b), quadriceps femoris, i.e., vastus lateralis, vastus intermedius, rectus femoris, and vastus medialis, with peripheral muscle fat replacement of the vastus lateralis in a sandwich pattern (yellow arrow in b), severe involvement of semimembranosus, semitendinosus, and biceps femoris long head with preservation of biceps femoris short head (green arrow in b), sartorius (yellow asterisk * in b) and gracilis (blue asterisk * in b). c Legs with severe muscle fat replacment of soleus and gastrocnemius medialis (yellow arrow in c), with partial preservation of gastrocnemius lateralis (green arrow in c). STIR-weighted axial Magnetic resonance imaging of the pelvis (d), thighs (e), and legs (f). Thighs with increased signal in left sartorius (yellow arrow in e). Legs with increased signal in tibialis anterior (yellow arrow in f), extensor groups, peroneous groups, and soleus. Western blot with calpain (g and h) and dysferlin (i and j) antibodies of control (g and i) and patient (h and j) with complete negativity of calpain expression in the patient (yellow arrow in h), compared to the control (g) with normal expression of dysferlin in the patient (yellow arrow in j) and in control (i). Right tibialis anterior muscle biopsy (k, l, m, n, o, p, q, r, s, t, u, and v) presenting muscle fibres with rimmed vacuoles (arrows in k and l), necrosis and phagocytosis (arrow in m), myofibre splitting (arrow in n), subsarcolemmal mitochondrial accumulation (arrow in o), oxidative irregularities in moth eaten pattern (arrows in p and q), increased acid phosphatase activity (arrow in r), focal areas of decreased intensity of dysferlin sarcolemmal membrane reaction (black arrows in s) in the same non-necrotic muscle fibres (*) analyzed in serial sections for spectrin (black arrow in t). Sarcolemmal membrane irregularities and subsarcolemmal mitochondrial accumulation (arrow in u) characteristic of lobulated fibres could be observed as well as irregular nucleus with indentations (arrow in v). (a, b, and c T1-weighted magnetic resonance imaging, d, e, and f STIR-weighted magnetic resonance imaging, g and h Western blot with calpain antibodies, i and j Western blot with dysferlin antibodies, k. HE 100x, l. HE 400b, m. Modified Gomori Trichrome 200x, n. ATPase pH 4.6 100x, o. SDH 100x, p. COX-SDH 100x, q. NADH 100x, r. Acid phosphatase 100x, s. Immunohistochemistry anti-dysferlin antibody 400x, t. Immunohistochemistry anti-spectrin antibody 400x, Transmission Electron Microscopy u. 2,500x, and v. 8,000x)