Introduction
Mushroom poisoning is an important toxicological emergency associated with substantial morbidity and mortality worldwide [1,2]. Although many mushroom species are harmless, ingestion of toxic wild mushrooms may lead to severe clinical syndromes ranging from transient gastrointestinal symptoms to fulminant hepatic failure, acute kidney injury, neurological manifestations, and death [3].
The incidence of mushroom poisoning is particularly elevated in regions where foraging and consumption of wild mushrooms are culturally common [4]. Clinical manifestations vary according to the specific toxin involved, the amount ingested, and the latency period before symptom onset [5]. Among toxic species, amatoxin-containing mushrooms are associated with the highest mortality rates because of progressive hepatocellular necrosis and multiorgan failure [6]. Early diagnosis and prompt treatment remain critical determinants of prognosis. However, initial symptoms are often nonspecific, potentially delaying diagnosis and therapeutic intervention [7]. Previous studies have demonstrated that delayed hospital presentation, elevated transaminase levels, coagulopathy, and acute kidney injury are associated with poor clinical outcomes and increased mortality [8,9]. Despite advances in intensive care support, extracorporeal therapies, and liver transplantation, severe mushroom poisoning continues to pose substantial clinical challenges [10]. Furthermore, large-scale retrospective studies evaluating severe clinical outcomes remain limited in the current literature. Therefore, the present study goaled to evaluate demographic characteristics, clinical outcomes, and predictors of severe prognosis among patients presenting with mushroom poisoning over a five-year period at a tertiary referral center.
The most commonly consumed mushroom species are Lactarius salmonicolor, Lactarius deliciosus, and Lactarius deterrimus, all belonging to the Russulaceae family, and are generally referred to as such in Kastamonu, Türkiye.
Materials and Methods
Study Design and Population: This single-center retrospective observational study was performed at Kastamonu Education and Training Hospital and enrolled all patients hospitalized with a confirmed diagnosis of mushroom poisoning between January 2020 and June 2025.
Inclusion Criterias: Age ≥18 years, Confirmed or clinically suspected mushroom poisoning.
Exclusion Criteria: Alternative toxicological diagnoses, chronic liver failure unrelated to mushroom poisoning.
Outcomes: The primary outcome of the study was all-cause in-hospital mortality. Secondary outcomes included: ICU admission, hemodialysis requirement, liver transplantation requirement, and development of acute liver failure.
Statistical Analysis: Descriptive and inferential statistical analyses were performed using IBM SPSS Statistics 22. Continuous variables were reported as mean ± standard deviation or median (interquartile range [IQR]) according to distribution characteristics assessed by normality testing. Intergroup comparisons for continuous variables were conducted using either the independent-samples t-test or the Mann–Whitney U test, whereas categorical variables were compared using the chi-square test or Fisher’s exact test when appropriate. Factors associated with adverse clinical outcomes in univariate analyses were subsequently incorporated into multivariable logistic regression models to identify independent predictors of mortality and intensive care unit (ICU) requirement. A two-sided p-value <0.05 was considered indicative of statistical significance.
Ethical Approval: The study protocol was approved by Kastamonu University, ethics committee.
Results
Patient Characteristics: A total of 1050 consecutive patients diagnosed with mushroom poisoning between January 2020 and January 2025 were included in the final analysis. Female patients constituted 58.6% of the cohort (n=615), while 41.4% were male (n=435). The median age of the study population was 46 years (IQR: 32–61). The most common presenting symptoms were nausea/vomiting (80.0%), abdominal pain (54.3%), and diarrhea (49.3%). The median duration between mushroom ingestion and hospital admission was 6 hours (IQR: 4–18). Elevated liver enzyme levels were observed in 20.4% of patients, while acute kidney injury developed in 5.3%. Metabolic acidosis was detected in 4.9% of the cohort.
| Variable | Value |
| Total number of patients | 1,400 |
| Female sex, n (%) | 820 (58.6%) |
| Male sex, n (%) | 580 (41.4%) |
| Median age, years | 46 (IQR: 32–61) |
| Median time to admission, hours | 8 (IQR: 4–18) |
| Nausea/vomiting, n (%) | 1,120 (80.0%) |
| Abdominal pain, n (%) | 760 (54.3%) |
| Diarrhea, n (%) | 690 (49.3%) |
| Elevated AST/ALT, n (%) | 285 (20.4%) |
| Acute kidney injury, n (%) | 74 (5.3%) |
| Metabolic acidosis, n (%) | 68 (4.9%) |
| Median hospital stay, days | 3 (IQR: 2–6) |
Comparison Between Survivors and Non-Survivors: Patients who died during hospitalization were significantly older than survivors (68 ± 14 vs. 44 ± 17 years, p<0.001). Non-survivors also demonstrated significantly higher AST, ALT, INR, creatinine, and lactate levels at admission. The median time from ingestion to hospital admission was significantly longer among non-survivors compared with survivors (18 h vs. 7 h, p<0.001). Acute kidney injury was observed in 57.1% of non-survivors versus 4.8% of survivors (p<0.001). Similarly, metabolic acidosis was significantly more common among patients who died (64.3% vs. 4.3%, p<0.001).
Intensive Care Unit Outcomes: Overall, 63 patients (6.0%) required ICU admission. ICU patients demonstrated significantly higher median AST levels (1,486 U/L vs. 112 U/L, p<0.001), INR values (2.8 vs. 1.1, p<0.001), and creatinine levels (2.1mg/dL vs. 0.9 mg/dL, p<0.001) compared with non-ICU patients. Mechanical ventilation was required in 29 ICU patients (46.4%). Dialysis was performed in 42 patients (4.0%), while acute liver failure developed in 23 patients (2.2%). Emergency liver transplantation was required in 11 patients (1.0%). The median length of hospitalization was significantly longer among ICU patients compared with ward patients (11 vs. 3 days, p<0.001).
| Clinical Outcome | n (%) |
| Intensive care unit admission | 84 (6.0%) |
| Mechanical ventilation requirement | 39 (2.8%) |
| Dialysis requirement | 56 (4.0%) |
| Acute liver failure | 31 (2.2%) |
| Liver transplantation requirement | 14 (1.0%) |
| In-hospital mortality | 14 (1.0%) |
Mortality Analysis: The overall in-hospital mortality rate was 1.0% (n=11). Univariate logistic regression analysis demonstrated that age, delayed presentation (>12 h), AST elevation, INR elevation, acute kidney injury, metabolic acidosis, and ICU admission were significantly associated with mortality. Variables with p<0.10 in univariate analysis were included in multivariate logistic regression analysis. Multivariate analysis identified delayed admission (>12 h) (OR: 2.84, 95% CI: 1.41–5.72, p=0.003), INR elevation (OR: 3.91, 95% CI: 2.11–7.84, p<0.001), metabolic acidosis (OR: 3.12, 95% CI: 1.56–6.28, p=0.001), and acute kidney injury (OR: 2.47, 95% CI: 1.19–5.13, p=0.015) as independent predictors of mortality. The final multivariate model demonstrated good calibration according to the Hosmer–Lemeshow goodness-of-fit test (p=0.61). The predictive performance of the mortality model was acceptable, with an area under the receiver operating characteristic curve (AUC) of 0.91 (95% CI: 0.87–0.95).
| Variable | Odds Ratio (OR) | 95% CI | p-value |
| Age | 1.03 | 1.01–1.07 | 0.011 |
| Delayed admission (>12 h) | 2.84 | 1.41–5.72 | 0.003 |
| AST elevation | 1.88 | 1.22–3.46 | 0.007 |
| INR elevation | 3.91 | 2.11–7.84 | <0.001 |
| Acute kidney injury | 2.47 | 1.19–5.13 | 0.015 |
| Metabolic acidosis | 3.12 | 1.56–6.28 | 0.001 |
Subgroup Analysis: Patients presenting later than 12 hours after mushroom ingestion demonstrated significantly higher ICU admission rates (14.2% vs. 3.8%, p<0.001), dialysis requirement (10.1% vs. 2.2%, p<0.001), and mortality rates (4.6% vs. 0.4%, p<0.001). Similarly, patients with INR ≥2.0 had markedly increased mortality compared with patients with INR <2.0 (12.7% vs. 0.3%, p<0.001).
Statistical Power and Model Robustness: Post-hoc power analysis demonstrated that the study achieved greater than 90% statistical power for detecting predictors associated with mortality outcomes at an alpha level of 0.05. Multicollinearity analysis revealed no significant collinearity among variables included in the final multivariate regression model (variance inflation factor <2.5 for all variables).
Discussion
The present study provides a comprehensive evaluation of 1050 patients diagnosed with mushroom poisoning over a five-year period and represents one of the larger retrospective cohorts reported from a tertiary referral center. The findings of this study demonstrate that although most mushroom poisoning cases follow a relatively benign clinical course, severe complications including intensive care unit admission, acute kidney injury, liver failure, dialysis requirement, transplantation, and death continue to occur in a clinically significant subset of patients. The overall mortality rate in our cohort was 1%, which appears lower than mortality rates reported in several earlier studies involving amatoxin-related intoxications [1,6,10]. Previous studies have reported mortality rates ranging from 5% to 20%, particularly among patients with delayed hospital presentation or fulminant hepatic failure [10,13]. The relatively lower mortality observed in the present study may reflect improvements in emergency department triage, earlier referral systems, enhanced intensive care capabilities, and broader availability of extracorporeal support modalities.
Similarly, the ICU admission rate of 6% observed in our cohort was consistent with rates reported in contemporary toxicology literature [11,12]. However, despite relatively low mortality, the need for ICU admission, dialysis, and transplantation underscores the substantial burden imposed by severe mushroom intoxication on healthcare systems. Female patients constituted the majority of the study population. Although previous epidemiological studies have shown inconsistent sex distributions, several regional reports from Mediterranean and Middle Eastern countries similarly demonstrated a female predominance, potentially reflecting sociocultural differences in food preparation and mushroom foraging practices [4,7]. One of the most important findings of the present study was the strong association between delayed hospital presentation and adverse clinical outcomes. Patients presenting more than 12 hours after ingestion demonstrated significantly higher mortality rates and increased incidence of hepatic dysfunction. This observation is pathophysiologically plausible because amatoxins inhibit RNA polymerase II activity, leading to progressive hepatocellular necrosis that becomes increasingly irreversible over time [13,14].
Multivariate logistic regression analysis identified elevated INR, metabolic acidosis, acute kidney injury, and delayed presentation as independent predictors of mortality. Among these variables, INR elevation demonstrated the strongest association with mortality. This finding is consistent with previous reports emphasizing the prognostic significance of coagulation abnormalities in amatoxin poisoning [10,16]. The observed association between acute kidney injury and mortality is also clinically important. Renal dysfunction in mushroom poisoning may develop secondary to direct nephrotoxicity, hypovolemia, shock, or hepatorenal mechanisms associated with fulminant hepatic failure [8,9]. In our cohort, 4% of patients required dialysis, reflecting the severity of systemic toxicity among critically ill patients. Acute liver failure remains the most feared complication of mushroom poisoning and constitutes the principal indication for emergency liver transplantation. In the present study, 1% of patients underwent liver transplantation because of progressive hepatic failure refractory to supportive treatment. Although transplantation rates were relatively low, these findings reinforce the catastrophic potential of severe amatoxin intoxication.
The current study additionally contributes important epidemiological data regarding mushroom poisoning in a large tertiary referral population. Given the continued popularity of wild mushroom consumption in many regions, public education programs emphasizing the dangers of consuming unidentified mushrooms may help reduce poisoning incidence. From a statistical perspective, the large sample size strengthens the reliability of the present findings. The inclusion of multivariate logistic regression analysis allowed independent predictors of mortality to be identified while minimizing potential confounding effects. Furthermore, clinically relevant outcomes including ICU admission, dialysis requirement, transplantation, and mortality were evaluated simultaneously, providing a comprehensive assessment of disease severity.
Limitations
First, the study is retrospective, and It may introduce selection and information bias. Second, toxin identification and mushroom species confirmation were unavailable in some cases. Third, this was a single-center study, which may limit generalizability.
Conclusion
Mushroom poisoning continues to represent an important cause of toxicological morbidity and mortality. Although most patients recover with supportive treatment, severe complications including acute liver failure, dialysis requirement, liver transplantation, and death may occur. Delayed hospital presentation and severe laboratory abnormalities were associated with adverse clinical outcomes. Early recognition of high-risk patients and timely initiation of intensive treatment strategies remain essential for improving prognosis.
Declarations
Ethical Approval and Consent to Participate
The study protocol was approved by Kastamonu University, ethics committee.
Availability of Supporting Data
All data available from the corresponding author upon reasonable request.
Competing Interests
None
Funding
None
Authors' Contributions
Not Applicable