An atypical presentation of Lemierre syndrome in a child with nephrotic syndrome: a case report and literature review.

backgroundLemierre's syndrome (LS) is a rare but potentially fatal condition characterized by septic thrombophlebitis of the internal jugular vein (IJV) following oropharyngeal infection, with an estimated incidence of 3.6 cases per million population. It primarily affects healthy adolescents and young adults; pediatric presentations, particularly in children under ten, are exceedingly rare and frequently atypical, with a heightened risk of diagnostic delay and multisystem morbidity. Although orbital cellulitis and intracranial venous extension have each been individually described in pediatric LS, their combined occurrence together with culture-negative status and a prolonged, indolent clinical course remains sparsely documented in children under ten years of age. CASE PRESENTATION: We report a case of a previously healthy 6-year-old Asian male who presented to a tertiary pediatric hospital after approximately one year of intermittent fever and progressive left-sided facial swelling. Over the preceding 15 days, his illness acutely worsened, with the development of necrotic periorbital and facial lesions and chest pain, prompting emergency referral. On admission, generalized edema, hypoalbuminemia, and nephrotic-range proteinuria raised an initial working diagnosis of nephrotic syndrome, which reflected a true concurrent glomerular process, a hypercoagulable cofactor, or an epiphenomenon of prolonged systemic inflammation that could not be definitively resolved, as the family left the hospital before a complete nephrological work-up could be completed. Contrast-enhanced MRI of the brain and orbits demonstrated preseptal, periorbital, and facial soft tissue inflammation with diffusion restriction, along with loss of flow-void signal in the left sigmoid sinus and left IJV, indicative of thrombosis. Subsequent contrast-enhanced CT of the neck and chest confirmed left IJV thrombosis with septic pulmonary embolization, fulfilling the imaging criteria for Lemierre's syndrome with intracranial venous extension in the likely but not histologically or microbiologically confirmed setting of an oropharyngeal or dental portal of entry. Serial blood cultures yielded no bacterial growth, consistent with culture-negative LS in a child with probable prior antibiotic exposure, although the details of any treatment administered before referral could not be retrieved. The patient was managed with broad-spectrum intravenous antibiotics, subcutaneous enoxaparin, intravenous immunoglobulin, fresh frozen plasma, packed red cell transfusion, and albumin supplementation delivered through a multidisciplinary care pathway. Despite ongoing management, the family elected to leave against medical advice on day 19 of admission before a full antimicrobial and anticoagulation course could be completed.

conclusionsThis case illustrates an unusually indolent, culture-negative pediatric presentation at the interface of Lemierre-spectrum disease and complicated sepsis, combining a one-year prodrome, nephrotic-range proteinuria of uncertain primary etiology, orbital/facial and intracranial venous thrombosis, and septic pulmonary embolization in a 6-year-old child. Because several features deviate from the classic acute, oropharyngeal-onset picture of LS, we present this as a diagnostically challenging, atypical case rather than a textbook example, and we highlight how a superimposed hypercoagulable state, whether inflammatory, septic, or renal in origin, can blur the boundary between 'clean' LS and complicated pediatric sepsis. Maintaining a high index of suspicion for LS-spectrum vascular and septic complications in children with atypical, protracted facial or orbital disease, along with early imaging, prompt broad-spectrum antibiotic therapy, and coordinated multidisciplinary management, remains essential, even when the presentation departs from classic teaching.