Clinico-epidemiology of washing powder (‘Prinso’) poisoning in Sri Lanka

‘Prinso’ is a fabric stain remover, which is consisted of two sachets, one containing brown crystals (potassium permanganate) and the other white granules (calcium oxalate). The product is made by small scale manufacturers of Sri Lanka and has become popular as a remover of stains. Recently, deliberate self-poisoning with ‘Prinso’ has become common in both rural and urban areas of Southern Province of Sri Lanka. A prospective clinical study was conducted in Teaching Hospital Ratnapura, Sri Lanka over 3 years commencing from July 2017. Epidemiological data, clinical features, treatments, and outcomes were collected. The data were analyzed through SPSS software version 21, using descriptive statistics. There were 274 (9.5%) patients with ‘Prinso’ poisoning out of which 140 (51%) were males and 134 (49%) were females. All were deliberate self-poisonings and 117 (43%) ingested oxalate alone; 31 (11%) ingested only permanganate, and 126 (46%) ingested both chemicals. The age ranged from 13-80 years (mean 31.6 ± 14 years) and the most commonly affected age group was 12-31 years (165;60%). The majority of patients were unemployed (108;39%) and 22 (8%) schooling children. Most patients (n=145;53%) were admitted to hospital within 1-4 hour of the ingestion (median 2 hrs and IQR 2-4 hrs) from Ratnapura (n=74;27%). Most of them (n=78;28.5%) were treated at hospital for 3 days (mean 4.8 days, IQR 2-6 days). Decontamination was done for 88% (n=239). Gastrointestinal symptoms including nausea (n=90;33%), vomiting (n=193;70%) and epigastric pain (n=141;52%) occurred frequently. The main complications among the patients were acute kidney injury [AKI] (110;40%), hypocalcemia (38;14%), hypotension (29;11%), ECG changes (27;10%), and methemoglobinemia (26;9.5%). Hemodialysis was done for 39 (14%) and 20 (7%) were treated at intensive care unit from which 13 (5%) were intubated. Methylene blue (antidote) was given to 25 (9%). Leukocytosis was observed in 118 (43%) patients and 236 (86%) were recovered. Despite medical attempts, 22 (8%) died. Case fatality rate for ‘Prinso’ poisoning was found to be 6.6% (90% CI 2.3-13.4;P < 0.05). ‘Prinso’ is a deadly poisoning household agent and AKI is the most common clinical manifestation.