Significance of early diagnosis and surgical management in treating Mycobacterium immunogenum-related pyogenic extensor tenosynovitis: a case report.

BACKGROUND: Non-tuberculous mycobacteria (NTM) are environmental organisms that are increasingly contributing to human infections. Mycobacterium immunogenum, a variant of NTM discovered in 2001, is a rapidly growing mycobacterium that exhibits multidrug resistance. Reports of infections caused by this organism, particularly tenosynovitis in the musculoskeletal system, are limited. CASE PRESENTATION: A 71-year-old female with vesicular pemphigus, undergoing immunosuppressive therapy, presented with a progressively enlarging tumour on the dorsum of her right hand, along with erythematous papules that extended across her right forearm. The specimens of skin tissues and blood cultures revealed the presence of M. immunogenum. Magnetic resonance imaging evaluation led to the diagnosis of pyogenic extensor tenosynovitis. A multidrug regimen, comprising amikacin and clarithromycin, was initiated, followed by synovectomy. The patient underwent a course of 180 days of antimicrobial therapy and demonstrated no signs of disease recurrence one year after treatment completion. CONCLUSION: Early diagnosis and surgical intervention are crucial to prevent the adverse prognostic implications of pyogenic extensor tenosynovitis caused by M. immunogenum. Effective management requires precise microbial identification and susceptibility testing, necessitating collaborative engagement with microbiological laboratories.

Minocycline-Induced Hyperpigmentation: Importance of Early Diagnosis.

A 75-year-old woman on hemodialysis for end-stage renal failure due to polycystic kidney disease developed dark spots on her limbs. She had been treated for extended spectrum beta-lactamase-producing Escherichia coli bacteremia by a rectovaginal fistula and was on long-term oral minocycline (cumulative dose 45 g). Physical examination revealed dark patches on her forearms and lower legs but no trunk hyperpigmentation or visual impairment. Blood tests were normal. Skin biopsy confirmed minocycline-induced hyperpigmentation. Minocycline-induced pigmentation is categorized into types I-IV, each with unique clinical and histopathological features. Types I and II are reversible upon discontinuing minocycline, whereas types III and IV are permanent. The patient was diagnosed with type II pigmentation, generally occurring with a cumulative dose exceeding 70-100 g; however, her lower dose (45 g) led to pigmentation, possibly influenced by her vitamin D deficiency. Clinicians should evaluate the antimicrobial indication and treatment period, considering not only the benefits but also the side effects and antimicrobial resistance. If minocycline is used, attention should be paid to minocycline-induced hyperpigmentation, and this possibility should be communicated to patients to enable early detection.

Diagnostic accuracy of quick SOFA score and inflammatory biomarkers for predicting community-onset bacteremia.

The potential use of quick SOFA (qSOFA) score and inflammatory biomarkers as bacteremia predictors is unelucidated. Herein the aim of this study was to evaluate the diagnostic accuracy of the qSOFA score and biomarkers for predicting community-onset bacteremia. We enrolled adult outpatients with blood culture samples drawn between 2018 and 2020. Contamination, intensive care unit admission, and hemodialysis were excluded. We performed a case-control study, and analyzed 115 patients (58 with bacteremia and 57 without bacteremia). The positive likelihood ratio (LR) for bacteremia was 2.46 (95% confidence interval [CI] 0.76-9.05) for a qSOFA score ≥ 2, and 4.07 (95% CI 1.92-9.58) for tachypnea (≥ 22/min). The highest performing biomarkers were procalcitonin (area under the curve [AUC] 0.80; 95% CI 0.72-0.88), followed by presepsin (AUC 0.69; 95% CI 0.60-0.79), and C-reactive protein (AUC 0.60; 95% CI 0.49-0.70). The estimated optimal cut-off value of procalcitonin was 0.377 ng/mL, with a sensitivity of 74.1%, a specificity of 73.7%, and a positive LR of 2.82. Presepsin was 407 pg/mL, with a sensitivity of 60.3%, a specificity of 75.4%, and a positive LR of 2.46. Procalcitonin was found to be a modestly useful biomarker for predicting non-severe community-onset bacteremia. Tachypnea (≥ 22/min) itself, rather than the qSOFA score, can be a diagnostic predictor. These predictors may aid decision-making regarding the collection of blood culture samples in the emergency department and outpatient clinics.

Importance of early diagnosis and surgical treatment of calcified amorphous tumor-related native valve endocarditis caused by Escherichia coli: a case report.

BACKGROUND: Unlike Escherichia coli bacteremia, which is common, E. coli endocarditis is uncommon, particularly in patients with native valve, leading to its delayed diagnosis. CASE PRESENTATION: We present a case of infective endocarditis caused by E. coli in a 78-year-old Japanese man with type 2 diabetes, involving persistent bacteremia and vegetation on the mitral valve (measuring 18 × 4.2 mm in diameter). He presented with recurrent fever after antimicrobial treatment for pyelonephritis. He received antibiotic therapy for 6 weeks and required surgical removal of a calcified amorphous tumor and vegetation with mitral valvuloplasty 7 days after admission. Despite an episode of multiple cerebral infarctions, he recovered fully from the infection. CONCLUSIONS: Follow-up blood cultures should be performed for Gram-negative bacilli bacteremia among patients with unknown focus and an atypical clinical course after treatment. Early diagnosis and aggressive surgical intervention are paramount to achieving good clinical outcomes.

A non-immunocompromised host with nontuberculous mycobacteria-associated tubulointerstitial nephritis.

A 50-year-old man was admitted to our hospital with the complaints of fever and general malaise. He had no history of human immunodeficiency virus (HIV) infection or treatment with immunosuppressive agents. We performed renal biopsy to investigate possible acute kidney injury. Pathological findings showed inflammatory cell infiltration, including granulomatous lesions in the interstitium. We diagnosed the patient with acute granulomatous tubulointerstitial nephritis. We initiated prednisolone (PSL) 40 mg/day (0.6 mg/kg), in combination with isoniazid for a latent tuberculosis infection, because of positive results in interferon-γ release assays. The patient's fever and malaise promptly disappeared, and his renal function improved. After the patient had been discharged, Mycobacterium intracellulare grew in cultures of his renal tissue and urine. We gradually reduced the dose of PSL; we initiated combination therapy with ethambutol, clarithromycin, and rifampin. After 2 years of follow-up, the patient continued treatment for chronic kidney disease; it has since enabled him to avoid renal replacement therapy. This report describes a rare instance of nontuberculous mycobacteria-associated tubulointerstitial nephritis in a patient without a history of HIV infection or organ transplantation. In differential diagnosis of granulomatous tubulointerstitial nephritis, clinicians should consider drugs, sarcoidosis, tubulointerstitial nephritis and uveitis syndrome, vasculitis, and infections (e.g., involving mycobacteria). Prompt microbiological examinations, especially of urine or biopsy cultures, are vital for diagnosis.

Genomic insights into virulence factors affecting tissue-invasive Klebsiella pneumoniae infection.

BACKGROUND: The key virulence factors responsible for hypervirulent Klebsiella pneumoniae (hvKp) infection remains elusive. METHODS: We analyzed K. pneumoniae isolates collected between 2017 and 2019 and defined hvKp as a pyogenic infection. Classical K. pneumoniae (cKp) involved a non-invasive infection or uncomplicated bacteremia. Isolates belonging to the K. pneumoniae species complex were excluded. RESULTS: We analyzed 112 isolates, including 19 hvKp, 67 cKp, and 26 colonizers, using whole-genome sequencing. Population genomics revealed that the K1-sequence type (ST) 82 (O1v1) clade was distinct from that of the K1-ST23 (O1v2) clone. The virulence gene profiles also differed between K1-ST82 (aerobactin and rmpA) and K1-ST23 (aerobactin, yersiniabactin, salmochelin, colibactin, and rmpA/rmpA2). The K2 genotype was more diverse than that of K1. A neighboring subclade of K1-ST23 (comprising ST29, ST412, ST36, and ST268) showed multidrug resistance and hypervirulence potentials. Logistic-regression analysis revealed that diabetes mellitus was associated with K. pneumoniae infection (odds ratio [OR]: 4.11; 95% confidence interval [CI]: 1.14-14.8). No significant association was found between hvKp diagnosis and clinical characteristics, such as diabetes mellitus or community acquisition. However, the K1 genotype (OR: 9.02; 95% CI: 2.49-32.7; positive-likelihood ratio [LR]: 4.08), rmpA (OR: 8.26; 95% CI: 1.77-38.5; positive LR: 5.83), and aerobactin (OR: 4.59; 95% CI: 1.22-17.2; positive LR: 3.49) were substantial diagnostic predictors of hvKp. CONCLUSIONS: The K1 genotype, rmpA, and aerobactin are prominent predictors of hvKp, suggesting that further pyogenic (metastatic) infection should be examined clinically. These findings may shed light on key hvKp virulence factors.

Critical peritonitis secondary to gastrointestinal mucormycosis in a peritoneal dialysis patient: a case report.

Immunodeficient patients are susceptible to systemic fungal infections; however, these rarely cause secondary peritonitis. A 66-year-old man with multiple myeloma and diabetes mellitus on continuous ambulatory peritoneal dialysis (CAPD) presented with cloudy ascitic fluid. He had been treated with corticosteroids for 1 month for Tolosa-Hunt syndrome. We diagnosed peritoneal dialysis-related peritonitis caused by Enterococcus avium, removed the CAPD catheter, and initiated intravenous ampicillin. Computed tomography (CT) revealed an intramural gastric mass and a thinning ascending colon wall. Four days later, follow-up contrast-enhanced CT showed penetration of the ascending colon and rupture of the ileocolic artery. Emergency open surgery revealed hemorrhagic infarction with mucormycosis. We initiated intravenous liposomal amphotericin B 20 days after admission; however, he died 55 days later. Anatomical abnormalities, such as gastrointestinal perforation, should be considered for peritonitis in immunodeficient patients. Gastrointestinal mucormycosis is rare but fatal, resulting from a delay in diagnosis and consequent gastrointestinal perforation. For an early diagnosis and a favorable clinical outcome, it is important to consider the risk factors for mucormycosis, including corticosteroid use, diabetes, end-stage kidney diseases.

Postherpetic abdominal pseudohernia: A diagnostic pitfall.

The accurate diagnosis of postherpetic abdominal pseudohernia, the rare complication of herpes zoster, is essential to avoid unnecessary imaging studies or surgery. Close observation and waiting for complete recovery are warranted considering the disease's self-resolving nature and favorable prognosis.

Emergence of a daptomycin-non-susceptible Enterococcus faecium strain that encodes mutations in DNA repair genes after high-dose daptomycin therapy.

BACKGROUND: An increasing number of reports have documented the emergence of daptomycin-nonsusceptible Enterococcus in patients during daptomycin therapy. Even though several mechanisms for daptomycin-nonsusceptibility have been suggested, the potential genetic mutations which might contribute to the daptomycin-nonsusceptibility are not fully understood. CASE PRESENTATION: We isolated a vancomycin-susceptible, daptomycin nonsusceptible Enterococcus faecium strain from a patient with acute lymphocytic leukemia who received high-dose daptomycin therapy for E. faecium endocarditis. Whole-genome sequencing analysis revealed mutations within genes encoding DNA repair proteins MutL and RecJ of the daptomycin-nonsusceptible Enterococcus strain which might have facilitated its emergence. CONCLUSIONS: We identified the mutations of DNA mismatch repair genes in a clinical isolate of daptomycin nonsusceptible E. faecium which emerged in spite of high-dose daptomycin therapy. The finding implicates the possible association of DNA repair mechanism and daptomycin resistance. Careful monitoring is necessary to avoid the emergence of daptomycin non-susceptible isolates of E. faecium and particularly in cases of long-term daptomycin use or in immunocompromised patients.

Osteomyelitis due to Clostridium innocuum in a patient with acute lymphoblastic leukemia: case report and literature review.

INTRODUCTION: Clostridium innocuum is an anaerobic Gram-positive bacterium, unable to produce toxins and rarely causes infections. We report the first case of C. innocuum osteomyelitis and bacteremia in a patient with acute lymphoblastic leukemia (ALL). Findings were compared with previously reported cases of C. innocuum infections in immunocompromised patients, e.g., patients with acquired immune deficiency syndrome, leukemia, and organ transplantation. CASE DESCRIPTION: A 32-year-old Japanese male was admitted for persistent low-grade fever and purpura lasting for 1 month. Complete blood counts and cytogenetic analysis identified Ph1-positive ALL, which was successfully treated using chemotherapy. However, the patient developed high fever and lumbar pain during complete remission. Fluorodeoxyglucose-positron emission tomography and computed tomography demonstrated osteomyelitis. C. innocuum was identified as the causative agent and the patient was successfully treated using antibiotic therapy. DISCUSSION AND EVALUATION: We performed a literature review revealing a number of common aspects to the clinical presentation of C. innocuum infection and an association with various comorbidities. Further, we highlight the most efficient diagnostic and treatment strategies for C. innocuum osteomyelitis. CONCLUSIONS: Clostridium innocuum can be a causative pathogen of osteomyelitis and bacteremia in immunocompromised patients.