Identification and characterization of a novel α-haemolytic streptococci, Streptococcus parapneumoniae sp. nov., which caused bacteremia with pyelonephritis.

OBJECTIVES: We report a case of bacteremia with pyelonephritis in an adult male with an underlying disease caused by α-hemolytic streptococci. α-Hemolytic streptococci were isolated from blood, but it was challenging to identify its species. This study aimed to characterize the causative bacterium SP4011 and to elucidate its species. METHODS: The whole-genome sequence and biochemical characteristics of SP4011 were determined. Based on the genome sequence, phylogenetic analysis was performed with standard strains of each species of α-hemolytic streptococci. Digital DNA-DNA hybridization (dDDH) and average nucleotide identity (ANI) values were calculated. RESULTS: SP4011 showed optochin susceptibility and bile solubility, but did not react with pneumococcal omni antiserum. Phylogenetic analysis of the whole-genome sequence showed that SP4011 clustered with S. pneumoniae and S. pseodopneumoniae and was most closely related to S. pseodopneumoniae. Genomic analysis revealed that ANI and dDDH values between SP4011 and S. pseodopneumoniae were 94.0 % and 56.0 %, respectively, and between SP4011 and S. pneumoniae were 93.3 % and 52.2 %, respectively. Biochemical characteristics also showed differences between SP4011 and S. pseodopneumoniae and between SP4011 and S. pneumoniae. These results indicate that SP4011 is a novel species. CONCLUSION: Our findings indicate that SP4011 is a novel species of the genus Streptococcus. SP4011 has biochemical characteristics similar to S. pneumoniae, making it challenging to differentiate and requiring careful clinical diagnosis. This isolate was proposed to be a novel species, Streptococcus parapneumoniae sp. nov. The strain type is SP4011T (= JCM 36068T = KCTC 21228T).

Urine oxygenation predicts COVID-19 risk.

Since February, 2023, the omicron variant has accounted for essentially all new coronavirus infections in Japan. If future infections involve mutant strains with the same level of infectivity and virulence as omicron, the government's basic policy will be to prevent the spread of infection, without compromising socioeconomic activities. Objectives include protecting pregnant women and elderly persons, and focusing on citizens requiring hospitalization and those at risk of serious illness, without imposing new social restrictions. Although the government tries to raise public awareness through education, most people affected by COVID-19 stay at home, and by the time patients become aware of the seriousness of their disease, it has often reached moderate or higher severity. In this review, we discuss why this situation persists even though the disease seems to have become milder with the shift from the delta variant to omicron. We also propose a pathophysiological method to determine the risk of severe illness. This assessment can be made at home in the early stages of COVID-19 infection, using urine analysis. Applicability of this method to drug discovery and development is also discussed.

Pancreaticoduodenectomy after bilirubin adsorption for distal cholangiocarcinoma with severe obstructive jaundice refractory to repeat preoperative endoscopic biliary drainage: a case report.

The necessity of biliary drainage before pancreaticoduodenectomy remains controversial in cases involving malignant obstructive jaundice; however, the benefits of biliary drainage have been reported in cases with severe hyperbilirubinemia. Herein, we present the case of a 61-year-old man suffering from jaundice due to distal cholangiocarcinoma. In this case, obstructive jaundice was refractory to repeat endoscopic drainage and bilirubin adsorption. Hyperbilirubinemia persisted despite successful implementation of biliary endoscopic sphincterotomy and two rounds of plastic stent placements. Stent occlusion and migration were unlikely and oral cholagogues proved ineffective. Owing to the patient's surgical candidacy and his aversion to nasobiliary drainage due to discomfort, bilirubin adsorption was introduced as an alternative therapeutic intervention. Following repeated adsorption sessions, a gradual decline in serum total bilirubin levels was observed and pancreaticoduodenectomy was scheduled. The patient successfully underwent pancreaticoduodenectomy with portal vein resection and reconstruction and D2 lymph node dissection. After the surgery, the serum bilirubin levels gradually decreased and the patient remained alive, with no recurrence at 26 months postoperatively. Therefore, this case highlights the feasibility and safety of performing pancreaticoduodenectomy in patients with severe, refractory jaundice who have not responded to repeated endoscopic interventions and have partially responded to bilirubin adsorption.

Urinary liver-type fatty acid-binding protein level as a prognostic indicator of acute kidney injury secondary to severe falciparum malaria.

Acute kidney injury (AKI) secondary to severe falciparum malaria possesses a high mortality rate; however, a prognostic marker of renal dysfunction has not yet been identified. Thus, we reported a case of a patient with AKI secondary to falciparum malaria who underwent hemodialysis and a renal biopsy due to prolonged renal dysfunction. The male patient, in his 50 s, presented to our hospital with vomiting, diarrhea, fever, and decreased level of consciousness. The Giemsa-stained peripheral blood film revealed approximately 5% parasitemia, and a rapid diagnostic test was positive for Plasmodium falciparum. He was diagnosed with severe falciparum malaria and was started on quinine hydrochloride. Hemodialysis was initiated due to the decreased urine output and fluid retention. Subsequently, he was weaned off hemodialysis. The histopathological analysis of a renal biopsy revealed interstitial fibrosis, tubular atrophy, and chronic inflammatory cell infiltration; thus, malarial nephropathy was diagnosed. Thereafter, his renal function stabilized, and he was discharged from the hospital. The urinary liver-type fatty acid-binding protein (L-FABP) level decreased before renal function improved. Our report highlighted that long-term follow-up is essential for severe AKI secondary to malaria. The urinary L-FABP level may be a useful prognostic indicator of AKI secondary to severe falciparum malaria.

Blood perfusion with polymyxin B immobilized columns in patients with COVID-19 requiring oxygen therapy.

Extracorporeal blood purification with polymyxin B immobilized fiber column direct hemoperfusion (PMX-DHP), is reported to be effective in treating COVID-19 pneumonitis with oxygen demand. This multicenter prospective study evaluated the efficacy and safety of PMX-DHP in oxygen-requiring patients with COVID-19 admitted between September 28, 2020, and March 31, 2022. The primary endpoint was the percentage of clinical improvement 15 days after treatment. The secondary endpoint was the percentage of worsened disease status. Data from the COVID-19 patient registry were used for the synthetic control group. The improvement rate on Day 15 did not differ between PMX-treated patients and controls; however, the deterioration rate was 0.38 times lower in the PMX-treated group, and the death rates on Day 29 were 0 and 11.1% in the PMX-treated and control groups, respectively. The PMX group showed a 0.73 times higher likelihood for reduced intensive care demand, as 16.7% of PMX-treated patients and 22.8% of controls worsened. After treatment blood oxygenation improved, urinary ß2-microglobulin and liver-type fatty acid-binding protein showed significant decreases, and IL-6 decreased once during treatment but did not persist. In this study, PMX treatment effectively prevented the worsening of COVID-19 pathology, accompanied by improved oxygenation. PMX treatment to remove activated cells may effectively improve patient outcomes.

A retrospective study describing the effective exchange of total blood plasma for disease control in the exacerbation of serpiginous choroiditis.

INTRODUCTION: Serpiginous choroiditis presents with large yellow-white exudative lesions that occur near the optic nerve papillae, that progresses slowly with repeated relapses and cures. Although infection and autoimmunity have been implicated, the cause is unknown. METHODS: A man was diagnosed with serpiginous choroiditis on clinical and other examinations. He started treatment with oral corticosteroids, cyclophosphamide, adalimumab, azathioprine, rituximab, and mycophenolate mofetil. Only the steroids and cyclophosphamide had a therapeutic effect. Plasma exchange was initiated, and the lesions quickly resolved. RESULTS: Disease control has been maintained by plasma exchange and cyclophosphamide during flare-ups in the fall and winter, suggesting that plasma exchange is effective in the treatment of serpiginous choroiditis. CONCLUSION: The reproducible response with each recurrence suggests a strong association between the disease and autoimmunity. Furthermore, that some, as yet unknown, autoantibodies are involved in the pathogenesis of serpiginous choroiditis.