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.

Is trimethoprim/sulfamethoxazole-associated increase in serum creatinine a pseudo-elevation or true nephrotoxicity?

INTRODUCTION: The aim of this study was to determine the rates of trimethoprim/sulfamethoxazole (TMP/SMX)-associated pseudo-elevation and true nephrotoxicity by comparison of creatinine-estimated and cystatin C-estimated GFRs (glomerular filtration rates) before and after TMP/SMX administrations. METHODS: Patients in whom serum creatinine and cystatin C were simultaneously measured are the cohort of this study. A decreasing of creatinine-estimated GFR posterior to TMP/SMX by ≥ 20% and a decreasing of cystatine C-estimated GFR posterior to TMP/SMX by ≥ 20% were defined as true nephrotoxicity. A decreasing of creatinine-estimated GFR posterior to TMP/SMX by ≥ 20% and a decreasing of cystatine C-estimated GFR posterior to TMP/SMX by < 20% were defined as pseudo-elevation. RESULTS: A total of 66 patients were enrolled. Within the 19 patients in whom serum creatinine and cystatin C were measured simultaneously both before and after TMP/SMX administrations, 10 patients (52.6%) had nephrotoxicity. Fewer random error and systematic bias between creatinine- and cystatine C-estimated GFR were observed after TMP/SMX than before TMP/SMX by Bland-Altman analysis. CONCLUSIONS: Using cystatin C, we reveled TMP/SMX-associated nephrotoxicity is not uncommon. We should equally pay attention to TMP/SMX-associated nephrotoxicity and pseudo-elevation. In spite of pseudo-elevation, creatinine-estimated GFR after receiving TMP/SMX is ironically reliable as surrogate maker for renal clearance.

Clinical pharmacokinetic and pharmacodynamic analysis of daptomycin and the necessity of high-dose regimen in Japanese adult patients.

The objective of this study was to explore the optimal dosage regimen of daptomycin and to determine the necessity and validity of a high-dose regimen from the perspectives of PK/PD parameters using Monte Carlo Simulation (MCS) and therapeutic drug monitoring (TDM) in a Japanese clinical setting. The volume of distribution (0.13 ± 0.012 L/kg) in this study was greater than that in healthy volunteers reported in Japan. The range of half-lives was between 8.9 and 34.9 h, which were gradually prolonged as creatinine clearance decreased. In MCS, the cumulative fractions of response (CFR) of the peak/MIC â‰§ 60 and the AUC/MIC â‰§ 666 at the 6 mg/kg q 24 h were 72.0% and 78.8% but at the 10 mg/kg q 24 h, the CFRs improved to both 99%. In TDM with 6 mg/kg q 24 h regimen, the patients who reached the peak and AUC target were 40% (2 out of 5 patients), respectively. The intraindividual variability in daptomycin PK may indicate the necessity of TDM and high-dose regimen, such as over 8 mg/kg, may be needed to ensure the effectiveness especially on Japanese patients with normal renal function.

[A Case of Vibrio vulnificus Infection Improved with Conservative Treatment in Kagoshima].

We herein report on a case of Vibrio vulnificus infection that was improved by conservative treatment in Kagoshima, Japan. A 75-year-old Japanese woman with liver cirrhosis presented to our hospital with shaking chill and right lower leg pain. Her blood culture was positive for V. vulnificus, and bullae had newly appeared on the right leg. Further history taking revealed that she had eaten some raw seafood before admission. She recovered following administration of antibiotics and small incisions in the lesion. West Japan (especially, the northern parts of Kyushu island) is well known as an endemic area of V. vulnificus infection: however, some cases had been reported in other areas in Japan. When clinicians treat cellulitis with risk factors, we should consider the possibility of V. vulnificus infection, even in a non-endemic area. Taking blood culture and early administration of appropriate antibiotics may contribute to conservative cure of some case of V. vulnificus infection.