BACKGROUND Many ant species can harm humans; however, only a few cause life-threatening allergic reactions. Normally, reactions caused by ants occur in patients who come into contact with ant venom. Venom contains various biologically active peptides and protein components, of which acids and alkaloids tend to cause anaphylaxis. Ant venom can cause both immediate and delayed reactions. The main histopathological changes observed in ant hypersensitivity are eosinophil recruitment and Th2 cytokine production. CASE SUMMARY A 70-year-old man was bitten by a large number of ants when he was in a drunken stupor and was hospitalized at a local hospital. Five days later, because of severe symptoms, the patient was transferred to our hospital for treatment. Numerous pustules were observed interspersed throughout the body, with itching and pain reported. He had experienced fever, vomiting, hematochezia, mania, soliloquy, sleep disturbances, and elevated levels of myocardial enzymes since the onset of illness. The patient had a history of hypertension for more than 1 year, and his blood pressure was within the normal range after hypotensive drug treatment. He had no other relevant medical history. Based on the clinical history of an ant bite and its clinical manifestations, the patient was diagnosed with an ant venom allergy. The patient was treated with 60 mg methylprednisolone for 2 d, 40 mg methylprednisolone for 3 d, and 20 mg methylprednisolone for 2 d. Oral antihistamines and diazepam were administered for 12 d and 8 d, respectively. Cold compresses were used to treat the swelling during the process. After 12 d of treatment, most pustules became crusts, whereas some had faded away. No symptoms of pain, itching, or psychological disturbances were reported during the follow-up visits within 6 mo. CONCLUSION This case report emphasizes the dangers of ant stings.

Introduction: Erythropoietic protoporphyria (EPP) is a rare photodermatosis mainly caused by deficiency of the enzyme ferrochelatase (FECH).We herein report a case of EPP associated with 2 novel mutations in FECH.Case presentation: A 15-year-old boy experienced pain and pruritus after sunlight exposure. He had occasional claret-red urine, hepatomegaly with increased alanine aminotransferase and aspartate aminotransferase levels, and an elevated free erythrocyte protoporphyrin level. He was treated with oral β-carotene and cholestyramine and avoidance of sunlight as much as possible.Discussion: Genome sequencing revealed 2 novel FECH mutations that had been inherited from his healthy parents. Pathogenicity analysis involving prediction using PolyPhen-2, SIFT, and Mutation Taster revealed that the 2 novel mutations were likely pathogenic. Although the patient's parents were healthy, they each had one of these 2 mutations. This finding is consistent with previous reports stating that individuals carrying low-expression alleles can be asymptomatic. The pathogenesis of the disease caused by these 2 mutations requires verification by larger and more detailed studies. Conclusion: Although the precise role of these mutations in EPP is not clear, the findings in the present case expand the genotypic spectrum of the disease.