大杉 泰弘

The superior aortic recess, a normal pericardial extension around the ascending aorta, can be misinterpreted as pathological findings on imaging studies, potentially leading to misdiagnosis of conditions such as Takayasu arteritis. We report a case of persistent fever and joint pain initially suspected of having Takayasu arteritis based on contrast-enhanced CT showing apparent aortic wall thickening. Laboratory tests showed elevated inflammatory markers (CRP: 7.07 mg/dL, WBC: 11,200/μL), microcytic anemia (hemoglobin: 7.8 g/dL), and thrombocytosis (platelets: 599,000/μL). Initial treatment with nonsteroidal anti-inflammatory drugs, sulfasalazine, and low-dose prednisolone was ineffective. Although contrast-enhanced CT suggested aortic wall thickening, a fluorodeoxyglucose positron emission tomography scan/CT revealed no uptake in this area, making a diagnosis of Takayasu arteritis unlikely. Radiological reassessment identified the structure as the superior aortic recess rather than aortic wall thickening, and the patient fulfilled Yamaguchi's criteria for adult-onset Still's disease with markedly elevated ferritin (3,459 ng/mL). Treatment with prednisolone 60 mg daily and subsequent addition of tocilizumab 480 mg weekly led to complete symptom resolution and normalization of laboratory parameters. This case highlights the importance of recognizing normal anatomical variants in radiological interpretation to avoid misdiagnosis, emphasizing the need for comprehensive diagnostic approaches incorporating clinical, laboratory, and appropriate imaging findings to distinguish between vascular pathologies and normal anatomical variants.

Hepatic encephalopathy (HE) is a neurological impairment that typically occurs in patients with liver dysfunction or portosystemic shunting. Diagnosing HE can be challenging since it requires a process of exclusion. Ammonia is considered a major contributor to HE, though ruling out HE solely based on ammonia levels has the potential for misdiagnosis.  Malignancy infiltration is uncommon as an etiology of HE, although there are reported cases of HE patients with pancreatic neuroendocrine tumors (PNETs) diagnosed by the presence of hyperammonemia. We report a case of a disoriented patient with a PNET and diffuse metastases to the liver who presented without hyperammonemia. After excluding possible etiologies of altered mental status, we diagnosed the patient with HE and started on lactulose, which improved his condition. PNET patients can experience HE without hyperammonemia, and a thorough evaluation to rule out other etiologies is necessary for the diagnosis.

OBJECTIVES: Multidrug-resistant (MDR) bacterial infections are highly prevalent among long-term care facility (LTCF) residents, and are thus important targets for antimicrobial stewardship. Diagnoses of urinary tract infections (UTIs), which are associated with antimicrobial use in these facilities, are not always made by physicians. Past epidemiologic studies have included asymptomatic bacteriuria together with UTIs. The National Healthcare Safety Network has initiated a surveillance program to identify the causative organisms of UTIs in LTCF residents. In Japan, medical care for these residents is provided through in-person physician visits; however, limited related data are available. Therefore, we investigated the organisms causing UTIs and their drug susceptibility among LTCF residents in central Japan, and examined the prevalence of multidrug resistance, its risk factors, and correlations with clinical outcomes. METHODS: We retrospectively evaluated clinical and urine culture data of LTCF residents with physician-diagnosed UTIs between April 1, 2019, and April 30, 2022. RESULTS: The detection rate of multidrug-resistant organisms was high, with Escherichia coli being the most prevalent. Ceftriaxone was frequently used for initial therapy. The initial antimicrobial agents were significantly less active against MDR pathogens than non-MDR pathogens. Most residents continued to receive the initial agents regardless of culture results. Nonetheless, differences in the therapy duration, relapse and hospitalization rates, and death rate within 28 days between the multidrug-resistant and non-multidrug-resistant groups were not significant. CONCLUSIONS: Antimicrobial stewardship is essential for reducing antimicrobial use and selective pressure in LTCFs in Japan; however, more specific data are needed for its effective implementation.