[Cutaneous periarteritis nodosa recurring over a period of 30 years in streptococcal infections and progressing toward systemic vasculitis].

Introduction: Periarteritis nodosa (PAN) is a form of vasculitis affecting the small and medium-sized arteries. Below, we report a case of cutaneous PAN relapsing in streptococcal infections over a period of 30 years and progressing towards systemic vasculitis.

Case Report: A 35-year-old man was hospitalised for a retro-pharyngeal access associated with fever, arthralgia, myalgia and inflammatory subcutaneous nodules. Peripheral neurological signs were also seen with deficiency of the elevator muscles in the right foot. Examination of a biopsy from a nodule showed a characteristic image of PAN. Following drainage of the abscess, a favourable outcome was obtained with antibiotics and systemic corticosteroids. History taking showed that the patient had presented similar episodes since the age of 5 years involving arthralgia, myalgia and inflammatory subcutaneous nodules. These episodes appeared to follow a streptococcal infection, of which there was either clinical suspicion or objective elevation of antistreptolysin O (ASLO) titre. Skin biopsy resulted in diagnosis of cutaneous PAN 25 years earlier. In all cases, improvement was achieved by oral corticosteroids combined with treatment of the actual infection.

Discussion: In addition to the classic association with hepatitis B, and occasionally hepatitis C, PAN may be associated with streptococcal infections. The cases of post-streptococcal PAN described in the literature are predominantly cutaneous, although it is not rare to find associated arthromyalgia and sensory neurological impairment. We examined three cases of cutaneous PAN with long-term follow-up described in the literature. They began in childhood and the outcome was benign, with no systemic manifestations. Our case differed in terms of the appearance of motor neurological involvement.

Conclusion: Post-streptococcal PAN of childhood onset generally carries a better prognosis than adult systemic forms. However, our case shows that on rare occasions, there may be very long progression complicated by systemic involvement.