A rare case of purpura fulminans in an adult: Invasive meningococcal disease

Purpura fulminans (PF) is a life-threatening dermatological condition characterized by acute purpuric lesions and skin necrosis due to microvascular thrombosis. In adults, PF is most commonly triggered by severe sepsis, particularly caused by Neisseria meningitidis . Invasive meningococcal disease (IMD) frequently leads to PF in children but is rare in adults. Early recognition and treatment are essential to avoid severe outcomes. We present a rare case of PF in an adult with IMD, successfully treated without long-term complications. A 32-year-old woman with epilepsy, recently adjusted on higher doses of carbamazepine, presented with fever, vomiting, and convulsions. Her condition worsened with the development of high fever (40°C), hypotension, and generalized tonic-clonic seizures. Physical examination showed purpuric and petechial skin lesions on her limbs and extremities. Initial differential diagnoses included infectious PF (bacterial, particularly meningococcal or rickettsial), toxic epidermal necrolysis, and vasculitis. Laboratory findings revealed elevated C-reactive protein and neutrophil leukocytosis. Blood cultures confirmed N. meningitidis , and a skin biopsy demonstrated neutrophilic vasculitis with thrombosis consistent with PF. The patient was initially treated with intravenous fluids and empirical antibiotics (cefotaxime and doxycycline). After blood cultures isolated meningococci with sensitivity to cefotaxime, doxycycline was omitted. Despite the initial neurological decline, intensive care management resulted in full recovery. Necrotic skin lesions required specialized wound care and surgical debridement. Chemoprophylaxis was administered to close contacts and healthcare staff. IMD is a serious global health issue, with approximately 1.2 million cases reported annually. PF, a rare but severe complication of IMD, leads to skin necrosis and is associated with disseminated intravascular coagulation. Although predominantly affecting children, PF in adults remains rare, particularly in regions with low incidence of meningococcal disease. Diagnosis is based on clinical presentation, laboratory results, and microbial identification. In this case, blood cultures and polymerase chain reaction confirmed N. meningitidis , and the patient responded well to cefotaxime, consistent with known sensitivity patterns. PF is a severe manifestation of meningococcal disease. Early identification and aggressive treatment are critical for favorable outcomes. This case underscores the need for clinical vigilance, a multidisciplinary approach, and the efficacy of timely antibiotic intervention in managing meningococcal infections.