Chitosan-induced Cogan’s-like syndrome: a case series of two patients following peripartum haemorrhage

Dear Editor, Cogan’s syndrome is a rare systemic vasculitis characterized by interstitial keratitis and audiovestibular dysfunction. Systemic manifestations such as fever, cardiovascular or musculoskeletal symptoms may also occur. Although its aetiology remains unclear, current evidence supports an autoimmune mechanism triggered by molecular mimicry or aberrant immune activation [1]. Peripartum haemorrhage is the leading cause of maternal mortality globally [2]. Chitosan, a chitin-derived biopolymer, has gained widespread acceptance in Obstetric Medicine as a potent haemostatic agent [3]. In particular, CeloxPPH® gauze has been shown to be both safe and effective in managing severe vaginal lacerations, significantly reducing blood loss in peripartum haemorrhage [4]. However, recent observations suggest severe adverse effects may be associated with its use. We report two patients who developed severe Cogan’s-like syndrome after chitosan (Celox®)-tamponade for life-threatening postpartum haemorrhage during caesarean (C)-section. A 33-year-old healthy woman (G3P2) underwent elective C-section. Intraoperatively, an atonic haemorrhage was successfully controlled by intrauterine application of a Celox chitosan-based tamponade. Two hours post-operatively, the patient developed fever (39°C), visual disturbances, headache, dizziness and transient confusion, prompting tamponade removal. Despite appropriate symptomatic and antihistaminergic treatment, additional symptoms including tinnitus, arthralgia, visual field defects and fatigue occurred the following day, leading to interdisciplinary diagnostics: ophthalmological examination demonstrated bilateral keratitis with sclerouveitis and panuveitis with preretinal infiltrates (‘snow balls’) and optic disc swelling (Fig. 1A). Visual acuity was 20/80 (right eye [RE]) and 20/200 (left eye [LE]). Perimetry disclosed no visual field defects in RE and a classical nerve fibre bundle defect, mostly due to optic disc infarction, in LE. ENT evaluation revealed bilateral, high-frequency sensorineural hearing loss (Fig. 1B). Additionally, C-reactive protein (CRP) was elevated (220 mg/l [n < 3mg/l]). Infectious and autoimmune serology were unremarkable (including ANA, ENA, ANCA, sIL-2R).