Necrotizing myositis: highlighting the hidden depths - case series and review of the literature

Abstract

Background: Necrotizing myositis (NM) is a life-threatening emergency. It causes focal muscle necrosis without abscess formation or extensive involvement of the overlying fascia and soft tissue. It is a clinical diagnosis requiring a high index of clinical suspicion. Usual presentation can readily be mistaken to represent more benign pathologies such as muscular injury, viral myopathy or deep venous thrombosis. The clinical course following initial misdiagnosis is rapid deterioration into profound sepsis and progressive multiorgan failure. Prompt treatment is associated with favourable outcomes, but early diagnosis is challenging due to initial absence of cutaneous signs and symptoms. Delayed referral to surgeons with appropriate expertise results in higher morbidity and mortality. The cornerstones to treatment are complete surgical debridement, intensive care management and accurate antimicrobial therapy.

Methods: We report four cases of NM demonstrating classical scenarios of initial misdiagnosis, delays in referral and review by an experienced surgeon. A review of the current literature to aid with overall management is also included.

Results: Review of literature that revealed the most common presentation was antecedent prodromal flu-like symptoms followed by rapidly progressing focal muscle pain. Patients were initially misdiagnosed followed by rapid deterioration into profound sepsis before surgical opinion was obtained.

Conclusion: NM is a rare and potentially fatal disease that must be considered in the differential diagnoses of the young, healthy patient with acute limb pain and fever. A high index of suspicion will facilitate earlier management and reduce morbidity and mortality.

Keywords: bacterial myositis; muscle necrosis; necrotizing myositis; streptococcal myositis.