Factors associated with viral clearance periods from patients with COVID-19: A retrospective observational cohort study.

INTRODUCTION: Knowledge is limited on the virologic course of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, particularly the time taken for viral clearance and the optimal time to discontinue isolation. This study aims to identify the clinical and demographic factors influencing the time taken for viral clearance in patients with COVID-19 to determine the optimal isolation period. METHODS: This two-center retrospective observational cohort study was conducted between March 1 and June 31, 2020. Patients with COVID-19, which was confirmed by real-time reverse transcription polymerase chain reaction, were included. Data were extracted from medical records. The positive duration, which was defined as the period from the day of symptom onset to the negative conversion day, was assessed using a generalized linear model. RESULTS: We included 63 patients. The mean positive duration was 20 days. The positive duration was significantly shorter for patients younger than 30 years of age and those between 30 and 60 years of age than for patients older than 60 years of age. We observed a more scattered distribution of the positive duration in older patients than in younger patients. CONCLUSIONS: Younger patients who recovered from COVID-19 took less time to clear SARS-CoV-2 than older patients; thus, a classification of the isolation periods based on age could be considered. A uniform viral clearance period for older patients may be difficult to determine because of biases such as underlying medical conditions. Further surveillance measures are recommended to determine the viral clearance time and the optimal isolation period.

Prevalence of Helicobacter pylori among residents and their environments in the Nara prefecture, Japan.

BACKGROUND: Chronic infection with Helicobacter pylori, specifically cagA-positive strains, is associated with gastric cancer. Thus, measures to prevent H. pylori infection are required. This study was conducted to clarify the prevalence of H. pylori in the community to identify the infection source and comprehensively assess the risk of H. pylori infection. METHODS: We collected 90 human faecal samples and 73 environmental samples (water, vegetable, and animal faecal samples) from the residents in an area with a high incidence of gastric cancer in Japan. Polymerase chain reaction assay was performed to detect the glmM housekeeping gene and the cagA virulence gene of H. pylori. A questionnaire survey was conducted, and the responses were analyzed statistically. RESULTS: The glmM gene was detected in 18 of 90 (20%) faecal samples obtained from residents; among them, the cagA gene was detected in 33.3% (6/18), and in all who had undergone eradication therapy. H. pylori was not detected in environmental samples. However, contact with dogs (OR 3.89, 95% CI 1.15-13.15, P < 0.05) was associated with higher odds for glmM gene positivity in the questionnaire survey. CONCLUSIONS: The prevalence of H. pylori and cagA-positive strains among the residents was low. However, the study results suggest a correlation between recurrent infection and cagA-positive H. pylori strains. Although H. pylori genes were not detected in living environments, an association between contact with dogs and a glmM positive status was revealed. Further investigations targeting community-dwelling healthy people and their living environments would be required for H. pylori infection control.

Clinical characteristics and molecular epidemiology of invasive Streptococcus agalactiae infections between 2007 and 2016 in Nara, Japan.

Invasive Streptococcus agalactiae (GBS) infections are increasingly common among neonates and the elderly. Therefore, GBS surveillance for better antibiotic treatment and prophylaxis strategies are needed. We retrospectively evaluated the clinical aspects of invasive infections and the phenotypic and genetic diversity of infectious isolates from Nara, Japan, collected between 2007 and 2016, by using information from hospital records. GBS strains collected from the blood and cerebrospinal fluid cultures were evaluated for capsular types, multi-locus sequence typing (MLST), antibiotic susceptibility, antibiotics resistance gene, and pulsed-field gel electrophoresis. Forty GBS isolates (10 from children and 30 from adults) were analyzed, and the distribution of molecular serotype and allelic profiles varied between children and adults. We found the rates of early-onset disease in neonates with birth complications to be higher than that of previous reports, indicating that there could be relevance between complications at birth and early-onset disease. Standard antibiotic prophylaxis strategies may need to be reconsidered in patients with birth complications. In adults, the mean age of the patients was 68 years (male: 63%). Primary bacteremia was the most common source of infection. In the neonates, six had early-onset diseases and four had late-onset diseases. The most frequently identified strains were molecular serotype Ia ST23 (40%) and molecular serotype Ib ST10 (20%) in children and molecular serotype Ib ST10 (17%), molecular serotype VI ST1 (13%), and molecular serotype V ST1 (13%) in adults. Levofloxacin-resistant molecular serotype Ib strains and molecular serotypes V and VI ST1 were common causes of GBS infection in adults but were rarely found in children. Furthermore, pulsed-field gel electrophoresis in our study showed that specific clone isolates, that tend to have antibiotics resistance were widespread horizontally for a decade. Continuous surveillance and molecular investigation are warranted to identify the transmission route and improve antibiotic treatment strategies.

Necessity to screen and treat latent tuberculosis before ruxolitinib treatment-Ruxolitinib-associated disseminated tuberculosis: A case report and literature review.

Ruxolitinib, a Janus kinase inhibitor, considerably improves symptoms of patients with polycythemia vera and primary or secondary myelofibrosis. However, its association with the development of infectious complications is a concern. Herein, we report the case of an 80-year-old man with primary myelofibrosis who developed disseminated tuberculosis during treatment with ruxolitinib at 15 mg twice daily and prednisone at 5 mg. We also reviewed the literature on patients who developed tuberculosis during treatment with ruxolitinib. There are 13 case reports of patients who developed tuberculosis during treatment with ruxolitinib, including our case. Disseminated tuberculosis manifestations were observed in 84.6 % of the patients and 50 % of them died. Although the interferon-gamma release assay was performed for seven of the patients with six positive results at the time of tuberculosis diagnosis, none were tested before the commencement of ruxolitinib. We suggest taking a history of tuberculosis and screening for and treating latent tuberculosis before administering ruxolitinib, especially in areas where the risk of tuberculosis is high.

Spinal epidural abscess caused by non-typhoidal Salmonella: A case report and literature review.

Non-typhoidal Salmonellae are Gram negative bacilli commonly causing self-limiting gastroenteritis, representing a public health issue particularly in tropical countries. Further, the epidemiology of invasive infection by non-typhoidal Salmonella species is poorly understood. Herein, we presented a case of an unusual Salmonella enterica subsp. enterica serovar Altona epidural abscess that cause osteomyelitis and psoas abscess in a 52-year-old Japanese man. To ensure adequate antibiotics penetration into the epidural space, the patient was treated with antibiotics in doses similar to those administered for meningitis. We also reviewed the literature on patients who developed non-typhoidal Salmonella epidural abscesses, and we found 10 other previously reported cases. Salmonella Enteritidis was the pathogen most commonly identified, similar to gastroenteritis. More surveillance of non-typhoidal Salmonella serovars, especially in cases of severe infection, and investigation of antibiotic penetration rate into the epidural space are warranted to decide the best treatment course.

Filifactor alocis brain abscess identified by 16S ribosomal RNA gene sequencing: A case report.

We report a clinical case of Filifactor alocis brain abscess in an 85-year-old man who had decayed teeth 1 week prior. In this case, the abscess was surgically drained after empirical antibiotics had been initiated. Although the causative organism could not be identified by culture, F. alocis was detected via 16S ribosomal RNA (16S rRNA) gene sequencing of the pus isolated from the abscess. The patient recovered without serious sequelae after surgical drainage and prolonged antibiotic treatment, including metronidazole, ceftriaxone and meropenem for 8 weeks. The findings in this case emphasize that 16S rRNA gene sequencing allows bacterial diagnosis of brain abscess when phenotypic identification fails, such as in cases where patients are undergoing antimicrobial treatment at the time of sampling or where patients are infected with fastidious organisms.

Development of a loop-mediated isothermal amplification assay for rapid Helicobacter pylori detection.

Infection with cagA-positive Helicobacter pylori is associated with gastric cancer. Molecular techniques are vital for accurate H. pylori diagnosis. We developed a loop-mediated isothermal amplification (LAMP) for detecting the H. pylori cagA gene and evaluated its use for clinical diagnosis. A LAMP primer set was designed to recognize the homologous regions of cagA gene sequences of 6 H. pylori strains. LAMP sensitivity was evaluated with serial dilutions of H. pylori ATCC 43504 and fecal specimens; specificity was evaluated with H. pylori ATCC 49396 and CIP 104086. The LAMP sensitivity for H. pylori specimens was 10-1 cfu/tube (reaction time, 37 min), which was 10-fold more sensitive than polymerase chain reaction. LAMP was also highly sensitive and rapid for fecal specimens. It detected cagA gene from ATCC 49396 and CIP 104086. The findings suggest LAMP can be used for diagnosing and screening of H. pylori infections to decrease gastric cancer incidence.

Case of endobronchial metastasis from breast cancer accompanied with Cunninghamella bertholletiae tracheobronchial mycetoma.

Cunninghamella is a member of the class Zygomycetes. Cunninghamella species include ubiquitous filamentous fungi; infections caused by Cunninghamella species are less frequent but have higher mortality rates than infections caused by Mucorales group members such as Rhizopus and Mucor. Herein, we reported a rare fatal case of endobronchial metastasis from breast cancer accompanied with Cunninghamella bertholletiae tracheobronchial mycetoma. A 73-year-old female with a history of right-sided breast cancer who had undergone mastectomy 11 years previously and had no recurrence presented to our emergency department with a 1-week history of left-sided back pain. Chest X-ray revealed left lung atelectasis; bronchoscopy revealed an endobronchial mass lesion in the left main bronchus. Pathological examination revealed fungal mycetoma but malignant lesions were not detected. Endobronchial and lung mycetoma caused by Cunninghamella bertholletiae were initially diagnosed; liposomal amphotericin B was administered, but her condition deteriorated. Rigid endoscopy showed growth of hemorrhagic tissue occupying the left main bronchus just under the carina. Pathological examination of the shaved lesion revealed metastasis from breast cancer covered with abundant necrotic tissue. No mold was observed in the necrotic tissue; this was probably due to liposomal amphotericin B treatment. To our knowledge, this is the first case of endobronchial metastasis from breast cancer accompanied with Cunninghamella bertholletiae mycetoma. Distinguishing endobronchial metastases from breast cancer and atypical presentations of Cunninghamella endobronchial mycetomas can be very difficult. Repeated bronchoscopies maybe helpful in establishing an accurate diagnosis when clinical prognosis does not match the initial diagnosis.

Molecular diagnosis and characterization of a culture-negative mycotic aneurysm due to ST54 Haemophilus influenzae type b with PBP 3 alterations.

Mycotic aneurysm is a rare but life-threatening disease that warrants an integrated therapeutic approach involving surgical intervention and prolonged antibiotic use. However, the causative organisms are often unidentified because antibiotics started empirically render blood and tissue cultures negative. Molecular diagnosis has been reported to be useful in such culture-negative cases. We report a case of a culture-negative mycotic aortic aneurysm due to Haemophilus influenzae, diagnosed by direct 16S rRNA polymerase chain reaction (PCR) and sequencing of the resected aneurysm tissue. PCR for serotype revealed type b, and PCR and sequencing of the ftsI gene revealed alterations in penicillin-binding protein 3, suggesting resistance to ampicillin. Multilocus sequence typing demonstrated that the isolate belonged to sequence type 54.

Development of Delayed Hemolytic Anemia After Treatment with Oral Artemether-Lumefantrine in Two Patients with Severe Falciparum Malaria.

AbstractRecently, reports of delayed hemolytic anemia after treatment with artemisinin and its derivatives have emerged. Here we report two cases of delayed hemolytic anemia in a patient with severe falciparum malaria after treatment with oral artemether-lumefantrine (AL). The first patient, a 20-year-old Japanese male student, was diagnosed with falciparum malaria and was administered AL. As having a high parasitemia rate (20.6%) was the only severe malaria criterion met in this case and his general condition was stable, we continued with AL treatment. Despite disappearance of malarial parasites after 4 days of AL administration, a persistent fever remained. On days 13 and 16, a diagnosis of hemolytic anemia was made (lactate dehydrogenase [LDH]: 1,466 U/L, hemoglobin [Hb]: 7.2 g/dL). A blood smear at that time revealed no parasites. He recovered naturally from delayed hemolysis. The second patient, a 27-year-old Japanese female student, was diagnosed with falciparum malaria (parasitemia: 4.5%) and treated initially with oral quinine hydrochloride and doxycycline. The following day, parasitemia increased to 7.9% and oral AL was initiated. She was discharged on day 4 after achieving parasite clearance and afebrility. However, on day 5, fever (body temperature > 38°C) recurred, and on day 11, a diagnosis of hemolytic anemia was made (LDH: 712 U/L, Hb: 8.8 g/dL). A follow-up confirmed that her condition improved gradually. AL treatment of severe malaria can cause delayed hemolytic anemia. Patients should be followed up for up to 4 weeks to detect signs of hemolysis and provide appropriate symptomatic treatment.

[A Case of Disseminated Cutaneous Mycobacterium chelonae Infection Successfully Improved with Thermal Therapy].

A 54-year-old female with dermatomyositis treated with cyclosporine and methylprednisolone presented with multiple subcutaneous nodules on her upper and lower extremities on December 2011. The number of lesions gradually increased. She had a history of surgical intervention such as debridement, skin graft of right lower leg due to trauma and subsequent bacterial infection on August 2011. Culture from a skin lesion on June 2012 confirmed Mycobacterium chelonae, which was susceptible to clarithromycin (CAM). We started treatment with CAM, imipenem/cilastatin (IPM/CS) and tobramycin (TOB) for 2 weeks. Then CAM monotherapy was continued, however CAM was discontinued because of liver dysfunction. In September 2012 new nodular lesions were observed on the left arm and right leg. We administrated azithromycin, IPM/CS and TOB. Subcutaneous nodules were partially improved, but new lesions appeared on her right leg. A culture of skin lesion yielded M. chelonae, which was highly resistant to CAM and IPM/CS. Based on the sensitivity test, moxifloxacin was used. However, there was no significant improvement in her skin lesions, so we started thermal therapy on day 57 after admission. She showed an excellent response to thermal therapy, and there has been no recurrence.

Chronic invasive sinus and intracerebral aspergillosis controlled by combination therapy with micafungin and a daily dose of 400 mg itraconazole oral solution.

Chronic invasive aspergillosis of the sinus is frequently fatal in the absence of early surgical and chemotherapeutic intervention because of its invasion of vascular tissue. We attempted to control a case of inoperable invasive aspergillosis of the sinus with micafungin and itraconazole oral solution. We prescribed a daily oral dose of 400 mg of itraconazole, which is twice the usual dose, and monitored the serum concentration of the drug. Finally, we were able to control the spread of the lesion. This case indicates that combination therapy with micafungin and a daily dose of 400 mg itraconazole oral solution is an alternative treatment strategy for inoperable invasive aspergillosis of the sinus.