Species identification, geographical distribution, poisoning symptoms and medical treatment of russula subnigricans

Abstract

Objective To study species identification, geographical distribution poisoning symptoms of russula subnigricans in order to provide guidelines of prevention and proper treatment. Methods Based on the data of epidemiological investigation, clinical treatment data and suspicious poisonous mushrooms, the collected mushroom were identified by morphological and molecular analysis, and the poisoning symptoms and medical treatment of R. subnigricans were systematically summarized. Results From the present two poisoning case, Epidemiological investigation showed that both patients ate some mushrooms in an appearance of fired charcoal(huotanjuncalled by layman) in the evening on July 26th, 2015. The incubation period was 2-3 hours. The main poisoning symptoms were nausea, vomiting, myalgia, typical soy urine, rapid increased in serum creatine kinase (CK), alanine transaminase (ALT), aspartate aminotransferase (AST), creatine kinase MB (CK-MB) and serum creatinine (sCr) were found. Finally patients fell in kidney failure and respiratory failure. All these symptoms met the typical manifestion of mushroom poisoning reported caused by R. subnigricans. These two patients were treated with hemoperfusion, continuous veno-venous hemofiltration (CVVH), liver protecting treatment, protective renal treatment and antioxidant therapy.One patient died after 40 days after admission.Other patient was transferred to a better facility and experienced physicians, and the other patient was still in hospital without any improvement up to the end of Feb. 2016 with a gloomy prospect. The mushroom eaten by the patients was identified as russula subnigricans though morphological and molecular analysis. Conclusions Russula subnigricans is a very toxic mushroom, widely distributed in southern China. Morphological and molecular analysis (using ITS sequence) is suitable for species identification of R. subnigricans. The incubation period of R. subnigricans poisioning is usually short, its target organ is mainly striated muscle, and severe patients usually have unfavourable outcome. Key words: Poisonous mushrooms; Russula subnigricans; Species identification; Geographical distribution; Medical treatment