Publications by authors named "Ken-Ichiro Kobayashi"

Article Synopsis
  • Japanese spotted fever (JSF), a tick-borne illness caused by Rickettsia japonica, has seen rising cases, with a notable cluster of seven reported for the first time in Japan's literature, linked to a cemetery visit in late 2019.
  • This outbreak was linked to an increase in cemetery visitors during a Buddhist event and a surge in infectious tick larvae, highlighting the role of environmental factors in disease spread.
  • Effective management of the outbreak involved prompt collaborative response from clinical, laboratory, and public health sectors, emphasizing the need for early intervention to prevent severe disease outcomes.
View Article and Find Full Text PDF

Background: Coronavirus disease 2019- (COVID-19-) associated cytotoxic lesions of the corpus callosum (CLOCCs) have been reported as a rare neurological abnormality in severe cases. Here, a case of CLOCCs in the early stages of mild COVID-19 infection during the Omicron BA.1 epidemic is reported along with a literature review.

View Article and Find Full Text PDF

While neck stiffness belongs to the classic triad of meningitis symptoms together with fever and altered mental status, it can also be attributed to inflammation from prevertebral space infection. We describe a difficult-to-diagnose case of prevertebral abscess associated with meningitis. Prevertebral space infection, vertebral osteomyelitis, and meningitis are reported to be associated with each other.

View Article and Find Full Text PDF

We describe the clinical features of a 75-year-old man who presented to our hospital with frequent urination for 3 months. Retrograde urethrography showed extended and continuous narrowing of the stricture in the anterior urethra. Cystourethroscopy showed extended narrowing of the urethral lumen without normal membrane.

View Article and Find Full Text PDF

Postpartum thyroiditis (PPT) is characterized by mild thyrotoxicosis occurring within one year of parturition commonly followed by transient hypothyroidism. Having genetic background of autoimmune thyroid disorders is a risk factor for it because the immune reactivation during postpartum period is a trigger for PPT. Pandemic of COVID-19: caused by SARS-CoV-2 infection is a global health problem, and occurrence of Graves' disease and Hashimoto's thyroiditis after the viral infection have been reported but occurrence of PPT with COVID-19 has never been reported.

View Article and Find Full Text PDF
Article Synopsis
  • * Two of the patients remained positive for the virus three weeks after their symptoms began, and all displayed bilateral ground glass opacities on CT scans.
  • * The report emphasizes the challenges of diagnosing COVID-19 based on common symptoms like fever and cough, suggesting that PCR tests and CT scans are essential for accurate diagnosis.
View Article and Find Full Text PDF

Background: In June 2013, the fear of adverse events compelled the government to withdraw its recommendation of the Human papillomavirus (HPV) vaccine. Since then, the rate of vaccination among Japanese girls has dropped dramatically.

Objective: This study aims to assess how the Japanese government's policy change against HPV vaccination influenced the degree to which parents in remote areas in Japan accepted the vaccine for their daughters, and to analyze related factors.

View Article and Find Full Text PDF

Purpose: To evaluate the diagnostic performance of chest CT to differentiate coronavirus disease 2019 (COVID-19) pneumonia in non-high-epidemic area in Japan.

Materials And Methods: This retrospective study included 21 patients clinically suspected COVID-19 pneumonia and underwent chest CT more than 3 days after the symptom onset: six patients confirmed COVID-19 pneumonia by real-time reverse-transcription polymerase chain reaction (RT-PCR) and 15 patients proved uninfected. Using a Likert scale and its receiver operating characteristic curve analysis, two radiologists (R1/R2) evaluated the diagnostic performance of the five CT criteria: (1) ground glass opacity (GGO)-predominant lesions, (2) GGO- and peripheral-predominant lesions, (3) bilateral GGO-predominant lesions; (4) bilateral GGO- and peripheral-predominant lesions, and (5) bilateral GGO- and peripheral-predominant lesions without nodules, airway abnormalities, pleural effusion, and mediastinal lymphadenopathy.

View Article and Find Full Text PDF

is a major causative organism of swine erysipelas, but the infection has rarely occurred in humans. A soft-tissue infection with this organism is described as "erysipeloid." Most reported cases in human are related to occupational exposure.

View Article and Find Full Text PDF

Gemella is a facultative anaerobic Gram-positive coccus and a rare cause of infective endocarditis (IE). Gram staining may eventually misidentify the organism, which tends to easily decolorize and manifest as either Gram-negative or Gram-variable. Commercial biochemical tests are often used to identify Gemella, but the methods they employ sometimes lack accuracy.

View Article and Find Full Text PDF

Most mediastinal abscesses result from infections after thoracotomy, esophageal perforation or pene- trating chest trauma. This disease is rarely caused by closed blunt chest trauma. All previously reported such cases after closed blunt chest trauma presented with hematoma and sternal osteomyelitis resulting from sternal fracture.

View Article and Find Full Text PDF

Six aspartic proteinase precursors, a pro-cathepsin E (ProCatE) and five pepsinogens (Pgs), were purified from the stomach of adult newts (Cynops pyrrhogaster). On sodium dodecylsulfate-polyacrylamide gel electrophoresis, the molecular weights of the Pgs and active enzymes were 37-38 kDa and 31-34 kDa, respectively. The purified ProCatE was a dimer whose subunits were connected by a disulphide bond.

View Article and Find Full Text PDF

Streptococcal toxic shock syndrome (TSS) is a systemic illness usually caused in the setting of infection by group A Streptococcus (GAS). The primary infections are often invasive infections of the respiratory tract or necrotizing infections of the skin and soft tissue, but some infections occur without relevant focus. GAS vaginitis is a rare condition among adult women and is accordingly thought to be uncommon as a cause of streptococcal TSS.

View Article and Find Full Text PDF

Hemophagocytic syndrome (HPS) can develop as a complication of dengue in rare cases, but its relationship with dengue is not well known. We report a case of dengue-associated HPS with liver involvement and coagulopathy. The patient, a Japanese female traveler who had recently returned from Thailand, had severe complications of dengue infection, but she recovered fully with symptomatic treatment.

View Article and Find Full Text PDF

Subjective adverse reactions to metronidazole were analyzed in 111 patients with amebiasis. Metronidazole was administered to 36 patients at a daily dose of 2250 mg and 75 patients at daily doses lower than 2250 mg. The reactions reported included nausea without vomiting in 11 (9.

View Article and Find Full Text PDF

The full-length cDNAs of three pepsinogens (Pgs) were cloned from the stomach of newt, Cynops pyrrhogaster, and nucleotide sequences of the full-length cDNAs were determined. Molecular phylogenetic analysis showed that two Pgs, named PgC1 and PgC2, belong to the pepsinogen C group, and one Pg, named PgA, belongs to the pepsinogen A group. The sequences contain an open reading frame (ORF) encoding 385 amino acid residues for PgC1, 383 amino acid residues for PgC2 and 377 amino acid residues for PgA.

View Article and Find Full Text PDF

In Japan azithromycin (AZM) has been used to treat enteric fever caused by bacteria with resistance to fluoroquinolones; however, the dose, length of treatment and effectiveness of AZM among Japanese patients with enteric fever is unclear. We studied 5 Japanese adults and 1 Japanese child with enteric fever (4 had typhoid fever and 2 had paratyphoid fever) who were treated with oral AZM. The treatment regimens were: 1,000 mg as a single or in 2 divided doses on the 1st day, followed by 500 mg as a single dose daily for 5-6 additional days, or 500 mg as a single dose daily for 10 days.

View Article and Find Full Text PDF

We report disseminated cysticercosis concurrent with taeniasis in a 31-year-old male Japanese, who had visited India three times and stayed for 1 month each time during the previous 1 year. The patient presented increasing numbers of subcutaneous nodules and expelled proglottids, although numerous cysts were also found in the brain in imaging findings, though no neurological symptoms were observed. Histopathological and serological findings strongly indicated cysticercosis.

View Article and Find Full Text PDF

Eight Japanese adult patients infected with Taenia asiatica were treated with a single 600 mg dose of praziquantel. The patients' body weights ranged from 47 to 87 kg (mean 67.1±12.

View Article and Find Full Text PDF

We treated a case of severe murine typhus in a Japanese traveler after returning from Thailand. Although the disease is typically self-limited or mild, the patient showed shock and multiple organ failure including acute respiratory distress syndrome. Then the patient fully recovered following intensive care and administration of antirickettsial medicines.

View Article and Find Full Text PDF