Fournier’s gangrene in a five year old boy – beware of the child post varicella infection

Abstract

Scrotal pain and swelling are common presentations in children and are usually secondary to torsion of the testis, hydatid of Morgagni or epididymo-orchitis. Fournier’s gangrene is a rare, but life-threatening disease, that can present in a similar fashion. We present a rare case of Fournier’s gangrene in a 5-year-old boy associated with a preceding varicella rash.

Case history

A 5-year-old boy presented to the paediatric assessment ward with a 3-day history of fevers and a rash; a diagnosis of chicken pox was made and he was discharged home with paracetamol and ibuprofen.

Two days later, he returned with pain, erythema and swelling of both his testicles. He was flushed and had a temperature of 37.9ºC and a pulse rate of 130 bpm. On physical examination, there were vesicular lesions all over his body, extensive erythema extending to his mid-thigh, and swelling of his scrotum with areas of purple discolouration. Laboratory tests showed a white blood cell count of 18,000/mm³ (normal, 6000–12,500/mm³) and a C-reactive protein of 237 mg/l (normal, < 6 mg/l). Antibiotics were commenced (clindamycin and benzylpenicillin) and he was taken to theatre for debridement. The devitalised tissue including the whole of his scrotum was excised. His testicles and cord were not affected and were preserved. The dead tissue was sent for microscopy and Gram-stain.

A second look in theatre the following day showed a small amount of necrotic tissue which was further debrided. He returned to the ward and the following day was constitutionally and clinically much improved. Blood culture and scrotal tissue confirmed Group A Streptococcus spp. and his antibiotics were continued for 10 days. Five days following his first debridement, a muscle flap and skin graft was performed by a plastic surgeon to repair the defect.

Discussion

Fournier’s gangrene is a necrotising fasciitis of the perineum which can rapidly spread to the skin of the entire scrotum and penis (1–2 cm/h). The process begins with focal skin infection and spreads along the fascial plane where inflammation, ischaemia, and necrosis result. This process was first described in 1883, by the French venereologist Jean Alfred Fournier. He described a series of five young men with progressive gangrene of the penis and scrotum, without apparent cause.^1,2 Despite knowledge spanning over two centuries, mortality remains high and averages 20–30%.³

Fournier’s gangrene is extremely rare in children. In adults, it is recognised that there are underlying predisposing conditions such as diabetes mellitus (most common), alcohol dependence, immunosuppressive therapy, long-standing steroid therapy, malnutrition, HIV, extremes of age and low socio-economic status. In children, it has been reported to be related to trauma, insect bites, circumcision, burns, appendicitis and systemic infection.^2,4,5 Fournier’s gangrene linked to varicella has only been described in three previous cases^4–6 and it is thought to occur as a result of secondary infection of the varicella vesicles.

The source of secondary infection may be urogenital (45%), anorectal (33%), or cutaneous (21%).⁵ Cultures from the wounds commonly show poly microbial infections by aerobes and anaerobes, which include coliforms, klebsiella, streptococci, staphylococci, clostridia, bacteroids, and corynbacteria.²

Chicken pox is caused by the varicella zoster virus; it is very contagious affecting almost all children, typically between 2–8 years of age. The child usually presents with fevers, generally feeling unwell and a characteristic rash all over the body. The rash initially develops as small, itchy, erythematous spots. These soon become fluid-filled blisters and, over a course of about 1–4 days, dry out and crust over. Varicella is usually self-limiting. Occasionally, the vesicles can become infected and develop uncomplicated cellulitis which would require broad-spectrum antibiotics. In more severe and rare cases, necrotising fasciitis can occur, most commonly affecting the lower extremities.⁷

Fournier’s gangrene is a true surgical emergency. Management involves prompt recognition and multimodal treatment including resuscitation, broad-spectrum antibiotics and surgical debridement. It must be stressed that early surgical debridement is the primary component of treatment and, if delayed, will have a negative impact on the prognosis.² All necrotic tissue should be excised until normal bleeding tissue is reached and multiple debridement undertaken as needed. The tissue should also be sent for culture so that antibiotic sensitivity can be obtained. Depending on the extent and the area of the tissue involved, urine and faecal diversion is sometimes indicated to allow for wound decontamination and healing.^2,4,5

The timing of secondary closure usually occurs once the infection has been completely eradicated and all dead-tissue debrided. In a child, superficial skin coverage alone is not always feasible as this may fail to develop with the developing underlying gonads. Options thus include full thickness skin grafts, axial groin flaps and myocutaneous flaps. In our case, the child underwent a full-thickness skin graft from a medial thigh donor site 5 days after his initial operation. He made a good recovery and was discharged home after a further 5 days.

Conclusions

Fournier’s gangrene is rare, especially in children, carrying a high mortality and morbidity. Varicella is a very common viral illness affecting most children. Awareness is needed in children presenting with scrotal pain and swelling with a history of preceding varicella infection. Early recognition and surgical debridement is the key to successful treatment.