Hydroxychloroquine‐induced autophagic vacuolar myopathy with mitochondrial abnormalities

Abstract

Hydroxychloroquine (HCQ) and chloroquine are used worldwide for malaria as well as connective and rheumatological disorders. They have been reported to be linked to myopathy in patients. We report four patients who were receiving HCQ as part of treatment for connective tissue disorder and who presented with myopathy. The muscle biopsy in these patients was consistent with findings of HCQ toxicity. HCQ muscle toxicity is usually self‐limiting after discontinuation of the drug. It also usually tends to be under‐reported due to presence of various confounding factors. This warrants close monitoring and consideration of muscle biopsy as part of initial work up of patients who present with myopathy while receiving HCQ.

The role of neutrophil extracellular traps and TLR signaling in skeletal muscle ischemia reperfusion injury

“…Although chloroquine-induced myopathy has been reported, this side effect is rare and reversible once the dosing regimen is stopped. 62,79,80 We found that daily dosing of 60 mg/kg HCQ for 7 days did not lead to mitochondrial dysfunction in the injured muscle, as assessed by COX/SDH double staining. Overall, HCQ decreased IL-10, TNFα, FAP proliferation, and ERK1/2 phosphorylation, which contributed to the pro-regenerative and anti-fibrotic effects observed.…”

Side Effects of Chloroquine and Hydroxychloroquine on Skeletal Muscle: a Narrative Review

“…This study demonstrated by OM the absence of vacuoles in half the sample (53.7%), which could be partially explained by the interval between the interruption of therapy and timing of the muscle biopsy beyond the technical difficulties in interpreting the biopsies. On the other side, their presence has also been described in other neuromuscular disorders, such as sporadic and familial inclusion body myositis, myofibrillary myopathy, oculopharyngeal muscular dystrophy, and some other myopathies [ 43 – 46 ].…”

Mechanisms of action of hydroxychloroquine and chloroquine: implications for rheumatology

“…The most common adverse effect of these antimalarial drugs are gastrointestinal effects, including nausea, vomiting, diarrhoea and abdominal discom fort 124 . In addition, several studies have reported the occurrence of hydroxychloroquineassociated myop athy [125][126][127][128] and hydroxychloroquinemediated and/or chloroquine mediated cardiotoxic effects, including rhythm disorders (such as a prolonged QT interval) and the development of cardiomyopathy in patients with rheumatic diseases [129][130][131][132] . However, conclusive evidence of cardiotoxicity caused by these drugs is lacking and further pharmacovigilance is required.…”