COVID-19 can lead to severe pneumonia, requiring mechanical ventilation. While increased sputum secretion could cause airway obstruction during mechanical ventilation, there are few reported cases in the literature. We report a case of a 65-year-old man with diabetes and severe COVID-19 pneumonia requiring mechanical ventilation and treated with hydroxychloroquine, azithromycin, nafamostat, and prone positioning. Initially, mechanical ventilation consisted of a heat moisture exchanger, endotracheal tube aspiration, and subglottic secretion drainage using a closed suction system. However, endotracheal tube impaction by highly viscous sputum occurred during this mechanical ventilation system. Replacing the endotracheal tube, the use of a humidifier instead of a heat moisture exchanger, and prone positioning contributed to the patient being weaned off mechanical ventilation. Although anti-aerosol measures are important for severe COVID-19 pneumonia, attention should be given to potential endotracheal tube impaction during mechanical ventilation.

Background Cytomegalovirus (CMV) is reported to have thrombogenic characteristics that activate factor X in vitro and stimulate the production of factor VIII and von Willebrand factor (vWF). Thrombosis associated with CMV infection is prevalent among immunocompromised patients and predominantly presents as a solitary large thrombus in the deep vein, pulmonary artery, splanchnic arteriovenous ducts, or other similar sites. Multiple thrombi, however, are rarely observed in such cases. Here, we report about an immunocompetent man with multiple microthrombi associated with CMV infection. Case presentation A 72-year-old Japanese man who complained of abdominal pain was hospitalized with multiple colonic stenosis. He was later diagnosed with CMV enterocolitis and treated with ganciclover from Day 27 post-admission. During hospitalization, the patient developed thrombi in his fingers. He was initially treated with anticoagulant therapy (rivaroxaban); however, the therapy was discontinued owing to a prolonged activated thromboplastin time and an elevated international normalized ratio of prothrombin time. Instead, vitamin K and fresh-frozen plasma were administered. Nevertheless, his coagulation profile remained abnormal. Eventually, he developed colonic perforation and had to undergo emergency surgery. An intraoperative specimen showed several microthrombi in the middle and small arteriovenous ducts of his small and large intestines. The patient’s coagulopathy improved preoperatively, and his overall condition improved postoperatively. Since the activation of ADAMTS13 was reduced remarkably, the thrombotic tendency was determined to be a thrombotic microangiopathy-like condition owing to increased vWF. We could not attribute the coagulopathy to any other cause except CMV infection; therefore, we concluded that this was a case of multiple thrombosis associated with CMV. Conclusions We present an extremely rare case of a patient with multiple thrombotic microangiopathy-like microthrombosis caused by CMV infection. Our findings suggest that CMV infection may be considered as a differential diagnosis for immunocompetent individuals who present with thrombosis of unspecified cause.

Background Acyclovir (ACV) neurotoxicity is a neuropsychiatric condition induced by the anti-herpetic drugs ACV and valacyclovir (VACV). It is presumed that elevated blood levels of ACV and its metabolite 9-carboxymethoxymethylguanine are involved in the development of ACV-induced encephalopathy; age and renal dysfunction are risk factors. Here, we report a case of encephalopathy caused by the administration of VACV for herpes zoster prophylaxis in a patient with renal dysfunction owing to multiple myeloma. Case Presentation Renal dysfunction was diagnosed in a 70-year-old man visiting our hospital for a medical checkup. His creatinine clearance rate was 8 mL/min. He was diagnosed with symptomatic multiple myeloma, and bortezomib/dexamethasone (BD) therapy for multiple myeloma and VACV for herpes zoster prophylaxis were initiated. We administered 500 mg/day of VACV three times a week, a lower dosage than recommended, after adjusting for his renal impairment. His renal function was monitored twice per week during therapy. During the second course of BD therapy, 6 weeks after starting treatment, he was hospitalized owing to impaired consciousness (Glasgow Coma Scale score: E2, V4, M4), and his BD and VACV therapy were suspended. Brain magnetic resonance imaging and cerebrospinal fluid analysis showed no abnormalities. Three days after discontinuing BD and VACV therapy, his consciousness recovered completely, and impaired consciousness did not recur after resuming BD therapy. His clinical diagnosis was thus ACV-induced encephalopathy. Conclusion VACV is often prescribed to patients with multiple myeloma receiving BD therapy to prevent herpes zoster. ACV-induced encephalopathy is commonly observed in patients with renal dysfunction; especially among patients with multiple myeloma with Bence–Jones proteinuria, renal tubules are easily damaged and plasma ACV concentrations are likely to increase and induce ACV-induced encephalopathy. Careful monitoring of the level of consciousness is necessary during preventive ACV therapy in patients with renal dysfunction.