Mushroom poisoning is an important global public health problem. There are approximately 5000 species of mushrooms, worldwide (
1). Approximately 4000 species of mushrooms have been classified in China, and approximately 400 species are considered poisonous (
2). It is very popular to consume wild mushrooms in many rainy areas due to their nutritional benefits and delicious taste. However, non-poisonous and poisonous mushrooms may be frequently mistaken for one another, leading to mushroom poisoning incidents. According to reports from the USA, there are approximately five wild mushroom exposures for every 100000 people, annually (
12). In China, data from the national food poisoning report of the Chinese Centers for Disease Control and Prevention (CDC) showed that 1954 mushroom poisoning cases were reported with a total of 409 deaths from 2004 to 2007. Mushroom poisoning was the main cause of death, and mortality was 20.93% (
13). The mortality rate varied from 10% to 90% in adults (
5,
14-
19). In the current report, the motality rate was 6.9% (4/58) in children. In this study, patients, who had severe clinical manifestations, were treated with gastric lavage and administered activated charcoal in addition to antibiotics (Penicillin G) and blood purification treatment. Blood purification treatment may be an effective treatment for reducing mortality in suspected mushroom poisoning patients (
6). In the group who died, the levels of WBC, total bilirubin, and number of involved organs were higher than those in the group who survived, yet the level of Hb was lower than that in the survived group. The ALT and AST levels, and total bilirubin seem to be an index of prognosis in children. The laboratory results of Cevik and Unluoglu (
20) indicated that blood urea nitrogen, creatinine, ALT and AST were higher in lethal and complicated cases. A number of articles (
7,
21,
22) have described factors associated with a greater possibility of death, including low sodium and high urea, AST, ALT, total bilirubin, PT, APTT, international normalized ratio, and lactate dehydrogenase.
In the current study, 63.79% of the patients consumed mushrooms in the summer. The results were consistent with previous studies (
6,
7,
15). In Sichuan province, the rainy season begins in the summer, which is when mushrooms are more frequently collected. Noting the high incidence of mushroom poisoning during summer may help doctors make an earlier diagnosis and take prompt action. In children, the first-noticed complaints of mushroom poisoning are gastrointestinal symptoms, which can be mistakenly diagnosed as common bacterial diarrhea. In the current study, all mushroom poisonings were due to the consumption of wild mushrooms. The pediatric patients frequently presented symptoms of nausea, vomiting, and abdominal pain. The other uncommon symptoms and signs included dizziness, delirium, headache, seizures, blurred vision, coma, jaundice, hypouresis and fever. Erenler et al. (
11) and Eren et al. (
7) reported similar results. These symptoms may help recognize MP early.
In the current study, there were 49 (84.5%) patients in the early-onset group and nine (15.5%) patients in the late-onset group. Moreover, the incidence of life-threatening exposure was higher in the late-onset group than that of the early-onset group. Colak et al. (
6) reported similar outcomes in adults. Life-threatening cases with late-onset syndrome poisoning are occasionally seen in Hong Kong district (
8). Late-onset syndrome includes hepatotoxic, nephrotoxic, and erythromelalgia syndromes (
10). The current study showed that three children suffering from mushroom poisoning died due to fatal hepatic failure. Amatoxin poisoning was suspected. Liver transplantation could be an optional treatment.
Notably, one patient died due to cardiac arrest. It could be assumed that he suffered myocardial toxicity. Because he died on hospital day two, the results of his liver function and renal function were almost normal. His K
+ level was 4.09 mmol/L. However, his values of cardiac markers were extremely high with a history of mushroom poisoning. Reportedly, he did not have a history of cardiovascular disease. Ren et al. (
23) suggested that mushroom poisoning symptoms should be classified to five types, gastroenteritis, acute renal failure, acute liver failure, psychoneurological disorders and hemolysis, based on the analysis of 3638 patients with mushroom poisoning from 1980 to 2002 in China. Chen (
15) reviewed 102 cases of mushroom poisoning from 1994 to 2012, and seven mushroom poisoning symptoms were suggested for clinical diagnosis and treatment: Gastroenteritis, acute liver failure, acute renal failure, psychoneurological disorder, hemolysis, photosensitive dermatitis and rhabdomyolysis. Based on the current study, it could be suggested that acute myocardial toxicity syndrome should be added to the list of mushroom poisoning symptoms. The researchers considered this kind of classification method to be appropriate. The identification of mushroom species can be very difficult in China. In the other countries, such as in the USA, the species identification rate was less than 6% (
24).
Myocardial toxicity from poisonous mushrooms can cause cardiac arrest and directly lead to death. Clinicians should pay attention to this circumstance. Additionally, in the study by Erenler et al. (
11), the most common Electrocardiogram (ECG) abnormalities were sinus tachycardia, sinus arrhythmia, and ST/T inversion in a group of 175 patients diagnosed with mushroom poisoning. However, cardiac makers were normal. In the current report, the values of cardiac makers in this patient were extremely high, yet his liver function was normal (
Table 4). It is unfortunate that the poisonous species consumed in this case could not be confirmed. Finally, there is a limited number of reports on cardiac toxicity, and more scientific observations are needed concerning toxicity of the heart due to mushroom poisoning.
5.1. Limitation of This Study
First, the toxin levels and mushroom species were not identified. Second, it is difficult to do the follow up visits for those who survived because most of these children came from rural areas of Sichuan province. Third, it was a retrospective study and only included small number of patients with late-onset symptoms.
5.2. Conclusions
Mushroom species are diverse, and various clinical manifestations occur based on mushroom species. Clinicians should take action towards early diagnosis and treatment. Children are at a high risk of exposure to wild and uncooked mushroom poisoning. Parents and children should be taught to avoid eating unknown, uncooked mushrooms from nature. Life-threatening poisoning cases are often encountered in patients with late-onset mushroom toxicity symptoms. Acute liver failure is the main cause of death, but doctors should not ignore myocardial toxicity.