Macrophagic Myofasciitis Plus (Distinct Types of Muscular Dystrophy)

Abstract

Macrophagic myofasciitis (MMF) is a well-known lesion following vaccination with aluminium-containing vaccines. It has abundantly been reported in adults and several times in children, often in single patients or in rather small cohorts. Only few of these published reports on children have shown distinct myopathology of another neuromuscular disease except for MMF. Indications for biopsy often were nondescript clinical features in children, such as hypotonia or delay in motor development but, apparently, never that of suspected MMF. Thus, in previous reports as well as in our two patients, encountering MMF in the biopsied tissue specimens was coincidental. Our two unrelated patients with MMF also had two separate types of muscular dystrophy, a merosinopathy and dystrophinopathy, showing a combination of myopathologically well-defined neuromuscular diseases, muscular dystrophies and MMF. Detecting such a combination of two separate conditions may, in the future, be rare when non-invasive techniques, e. g., genetic, will have replaced muscle biopsy in ascertaining hereditary neuromuscular conditions, especially in children.

Childhood macrophagic myofasciitis: A series from the Indian subcontinent

“…Most published reports of pediatric MMF have not documented any pathology apart from MMF. The only exceptions to this are the reports by Muller et al who identified merosin‐deficient congenital muscular dystrophy and Duchenne muscular dystrophy (DMD) coexistent with MMF in each of their 2 patients, and by Lach et al who diagnosed spinal muscular atrophy in 2 patients, and DMD, phosphoglycerate kinase deficiency, and cytochrome c oxidase deficiency in 1 patient each . Only 1 of our 6 patients had a coexistent neuromuscular disorder, merosin‐deficient congenital muscular dystrophy.…”

“…Pediatric cases of MMF are rare, as <50 cases have been reported . The clinical presentation of MMF in children is nonspecific, with most presenting with hypotonia or motor delay, as in our series . Rivas et al reported a time to onset of symptoms following vaccination of 1–3 months, with 71% of children having onset within 1 month of receiving vaccination .…”

“…The deltoid muscle was the biopsy site as well as the site for vaccination; HBV vaccine accounted for 84% of cases . Pediatric cases of MMF are rare, as <50 cases have been reported . The clinical presentation of MMF in children is nonspecific, with most presenting with hypotonia or motor delay, as in our series .…”

Macrophagic myofasciitis: characterization and pathophysiology

“…Occasional cases have been reported in many other countries. 8,[10][11][12][13][14][15] The structure of symptoms was strikingly similar in independent cohorts of French adult patients. 4 We recently reviewed the files of 457 adult MMF patients collected from 1994 to 2011 in our centre.…”

“…This point is particularly important in small children, who receive numerous alum-containing vaccine shots in the first year of life, increasing the risk of chance associations between MMF lesions and unrelated conditions, such as congenital myopathies and muscular dystrophies. 8 The risk also exists in adults, but accounts for no more than 5-10% of MMF-positive biopsies, including fully asymptomatic patients and patients investigated for hereditary disorders.…”