IS Case 150: Necrotizing fasciitis and Fournier's gangrene

Daniel T. O'Connor, MD

Imaging Sciences URMC 2008
Publication Date: 2009-05-21

History

A 77-year-old woman presented to an outside hospital with rapidly progressing bullous skin lesions of the left upper extremity and perineum with ashen appearance of affected limb and complete loss of function and sensation. Clinical suspicion/diagnosis of necrotizing fasciitis, and specifically Fournier's gangrene of the affected perineum. No history of immunosupression including diabetes mellitus. Cultures from the surgically debrided tissue were significant for a Clostridium ssp (not perfringens), B. fragilis, and multiple Staphylococcus ssp.

Findings

CT exam of the chest, abdomen, and pelvis demonstrated extensive soft tissue emphysematous changes with edema and infiltration of fluid compatible with aggressive soft tissue infection involving the left upper extremity to the deep tissues of the left lateral thorax and inferiorly within the perineal and perirectal soft tissues. Similar thickening of the bladder wall and sigmoid colon continuous with surrounding soft tissue changes.

Diagnosis

Necrotizing fasciitis and Fournier's gangrene

Discussion

Fournier's gangrene and necrotizing fasciitis are uncommon disease entities presenting as rapidly progressive and disfiguring soft tissue infections mediated by synergitic polymicrobial infections with reported mortality as high as 73%. A combination of virulent gram positive organisms, most commonly S. pyogenes/Group A streptococcis with concomitant gas-forming anaerobes, classically C. perfringens, cause the rapid disruption of connective tissue and extension along soft tissue planes typical of this disease. Vibrio vulnificus and Bacteroides fragilis are also commonly associated with the disease.

Diagnosis is clinical and represents a surgical emergency. Treatment almost universally involves rapid debridement of any and all affected tissue until only viable, well-perfused tissues remain with immediate initiation of broad spectrum anti-microbial therapy. Hyperbaric oxygen therapy is an increasingly common adjuvant treatment.

References

Kumar V, Fausto N, Abbas A. Robbins and Cotran Pathological Basis of Disease. 7th ed. Saunders, 2004.