The Geenius HIV-1/2 Confirmatory Assay (Geenius), which allows simultaneous detection of anti-HIV-1 and -2 antibodies has recently been introduced as a confirmatory test for HIV infection. Because of the limited number of patients with acute HIV-1 infection in whom this test has been conducted, further accumulation of information in patients with acute HIV-1 infection is required. In particular, the reliability and trend of the Geenius test results in each stage (six stages, I-VI) of the acute and early phase classification of HIV-1 infection (Fiebig stage, hereafter FS) and the characteristics of the associated viral pathological conditions are not yet fully understood. Herein, we report the results of a retrospective analysis conducted to clarify these issues.

First, since all cases after FS V showed an HIV-1-positive result, the confidence limit by Geenius was set at FS V. Next, we found unique relationships with pathological conditions in each FS: 1) a positive correlation was observed between the blood viral load (VL) and the signal-to-cutoff ratio (S/CO) of the fourth-generation screening test in the group of cases that was HIV-1-negative by Geenius; 2) a negative correlation between VL and CD4-positive T cell counts was found in the HIV-1-positive early case group, in whom the VL was significantly low. These observations suggest that the positivity rate by the Geenius assay in patients with acute-phase infection cases is correlated with the viral pathological features in each FS. These results may provide important information to clarify the relationship between the test results by the Geenius assay and the viral pathological conditions in patients with acute-stage HIV-1 infection.

During the COVID-19 pandemic, other countries reported a decrease in the number of hospitalizations for COPD. We compared the number of patients admitted to our hospital for COPD exacerbations in the 12 months before and after the onset of the pandemic, which was in March 2020. Patients admitted during the pandemic period were characterized by increased eosinophilia and histories of previous COPD exacerbations. The number of hospitalizations for GOLD 4 was similar before and after the onset of the pandemic.

A 62-year-old female patient under long-term corticosteroid therapy for systemic lupus erythematosus consulted our hospital for generalized malaise and was subsequently admitted to the hospital with the diagnosis of prerenal renal failure. During hospitalization, right lateral abdominal erythema and an elevated serum C-reactive protein level were observed. Chest computed tomography showed multiple nodular shadows in the right upper lung lobe. Thereafter, Cryptococcus neoformans was isolated from the blood and skin biopsy samples obtained from the erythematous region in the right lateral abdomen. Based on the findings, we established the diagnosis of disseminated cryptococcosis. Although the patient was immediately initiated on antifungal treatments, she developed cerebral infarction and pancreatitis, which were possibly attributed to the disseminated cryptococcosis. Subsequently, she rapidly developed evidence of disseminated intravascular coagulation syndrome and multiple organ failure, resulting in death. Herein, we report a case of disseminated cryptococcosis, in which detailed microbiological and pathological analysis was conducted.

Neonatal necrotizing enterocolitis is a fatal neonatal disease that accounts for a large proportion of deaths in the NICU. Preterm birth and low birth weight are among the most important risk factors, but the disease is multifactorial, with multiple other factors involved, including intestinal immaturity, ischemia, continued enteral feeding in place of breastfeeding, long-term exposure to antimicrobial agents, and an abnormal microbiota in the intestinal tract. In regard to the causative microorganism, the disease has been reported to be caused by Enterobacteriaceae such as Klebsiella pneumoniae and Clostridium perfringens type A.

There have also been reports of human necrotizing enterocolitis caused by C. perfringens type C, which is different from type A. However, all published reports are of cases in adults, not neonates. In the past, the disease was called Darmbrand or Pig-bel in Germany and Papua New Guinea highlands, and was considered as a zoonosis caused by the ingestion of large amounts of infected pork and other meats after World War II; nowadays, in developed countries, it is referred to as necrotizing enterocolitis, occurring especially in diabetic patients. The main cause of C. perfringens type C necrotizing enterocolitis is decreased trypsin concentration, which inactivates the beta toxin produced by C. perfringens, and the pathogenesis is different from that of neonatal necrotizing enterocolitis.

We report a case of necrotizing enterocolitis caused by C. perfringens type C in a neonate weighing 2,772 grams born after 36 weeks of gestation in a NICU in a developed country, without any contact with animals or the outside world.