Rationale: Although coronavirus disease 2019 (COVID-19) remains a global threat, administering effective and safe vaccines is currently the most promising strategy to curb the ongoing pandemic and decrease the number of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. However, there remains some uncertainty regarding the safety of vaccines for patients with kidney disease. Patient concerns: A 58-year-old man presented at our institution with gross hematuria 48 hours after receiving his first dose of the CoronaVac (Sinovac) vaccine. Diagnoses: Analysis of a renal biopsy sample led to the diagnosis of crescentic immunoglobulin A nephropathy (IgAN), which we considered an adverse event of receiving the CoronaVac vaccine in China. Interventions: The patient’s serum creatinine and albumin levels were 1.20 mg/dL and 31.3 g/L, respectively; as such, he was administered a diuretic. His serum creatinine level had risen to 7.45 mg/dL 1 month later, and he developed high blood pressure. The patient then received conventional doses of hormone therapy but developed recurrent fever, which led to the suspicion of active tuberculosis (which he had a history of) and suspension of the hormone therapy. Outcomes: The patient’s renal function deteriorated further, and he ultimately underwent dialysis. Lessons: The patient’s course of events of apparent IgAN exacerbation should prompt nephrologists to closely follow patients with glomerular disease after they receive a COVID-19 vaccine, especially if persistent gross hematuria occurs.

Rationale: Acquired neuromyotonia syndrome is a rare form of peripheral nerve hyperexcitability syndrome. It is characterized by spontaneous and continuous muscle contractions. Acquired neuromyotonia syndrome is mainly observed in patients with autoimmune diseases or tumors, but it is a rare neurological clinical manifestation in patients with mercury poisoning. Patient concerns: A 56-year-old woman presented with continuous and involuntary muscle twitching in her legs for 2 months; it was accompanied by a burning sensation in the lower limbs, insomnia, fatigue, and night sweats. These symptoms did not disappear during sleep. Diagnoses: Toxicological blood analysis via atomic fluorescence spectrometry revealed that the level of mercury was 0.07 μmol/L (normal level: <0.05 μmol/L). Her urinary mercury level measured using the cold atomic absorption method was 217.50 μmol/mol creatinine, which was considerably higher than the reference range (0–2.25 μmol/mol creatinine for people not in contact with mercury, 0–20 μmol/mol creatinine following long-term exposure). Upon further testing, a high level of mercury (10,572 mg/kg) was detected in the patient's cream. Accordingly, this patient was diagnosed with mercury poisoning. Interventions: Treatment with 2,3-dimercapto-1-propanesulfonic acid (DMPS) was initiated. Her urinary mercury level decreased to 9.67 μmol/mol creatinine, and her neuromyotonia syndrome and hyponatremia were relieved, with urine protein completely disappearing after 3 months of treatment. Outcomes: After DMPS treatment, the clinical manifestations of the nervous system disappeared and electrolyte parameters returned to normal levels. Lessons: Acquired neuromyotonia syndrome is a rare disorder caused by the hyperexcitability of peripheral nerves, resulting in spontaneous and continuous muscle contraction. Mercury poisoning should be considered in patients with neuromyotonia syndrome. Early detection of mercury poisoning can prevent unnecessary examinations and treatments.

Rationale: Upper gastrointestinal hemorrhage (UGIH) is defined as hemorrhage originating from the gastrointestinal tract proximal to the ligament of Treitz. The causes of UGIH include esophagitis, gastritis, peptic ulcers, Mallory-Weiss syndrome, and cancer. However, a rare cause of UGIH, such as an accessory spleen, may lead to serious complications if left untreated and can sometimes be very difficult to diagnose preoperatively.Patient concerns: An 18-year-old man was admitted to the Department of Gastroenterology of our hospital due to "repeated black stool for 2 months with aggravation, accompanied by hematemesis for 9 days." He denied any history of hepatitis, trauma, or surgery.Diagnosis: Laboratory evaluation revealed severe anemia (hemoglobin, 6.4 g/dL). Computed tomography revealed a mass measuring 127 mm in its largest dimension, located in the upper left abdomen, with varicose veins in the gastric fundus. Moreover, distended blue-purple tortuous veins were observed by gastroscopy in the gastric fundus. We believed the mass was likely an abnormally proliferating accessory spleen; however, the causes of severe anemia and gastrointestinal hemorrhage were unknown.Interventions: After discussion in a multidisciplinary conference, the mass was completely resected laparoscopically, and the subserosal veins in the gastric fundus were sutured using absorbable threads.Outcomes: After the surgery, the patient recovered uneventfully without any complications. Clinicopathological examination showed that the mass was chronic congestive splenomegaly. Gastrointestinal hemorrhage secondary to an abnormally proliferating accessory spleen was confirmed as the diagnosis. Laboratory evaluation revealed hemoglobin at 12.1 g/dL 2 months after surgery. At the 12-month follow-up, the patient showed no recurrence of gastrointestinal hemorrhage.Lessons: UGIH caused by accessory spleen is extremely rare. This entity should be considered in differential diagnosis of gastrointestinal hemorrhage. Surgical intervention is necessary for timely diagnosis and treatment in case of gastrointestinal hemorrhage in critical clinical situations.

Severe wasp sting symptoms can progress rapidly, often causing multiple organ dysfunction syndrome (MODS) and, in some cases, even death. Early and comprehensive treatment is needed to avoid these outcomes. Here, we report the case of a patient with MODS due to severe wasp stings. The patient received conventional treatment combined with glucocorticoids, plasma exchange, hemoperfusion, and continuous renal replacement therapy and had a successful recovery. MODS is a serious potential complication of wasp stings. Early local wound treatment, antiallergy interventions, antishock therapy, fluid replacement, glucocorticoid administration, and blood purification treatments are required to treat MODS secondary to wasp stings. Our results suggest that a hybrid blood purification method involving plasma exchange combined with hemoperfusion and continuous renal replacement therapy is more clinically effective than the single blood purification method. Early use of high-dose glucocorticoids combined with a hybrid blood purification treatment method had a positive effect in managing our patient and may improve the prognosis of other patients with MODS.