A High-risk Case of Culture-negative Infective Endocarditis with Severe Aortic Regurgitation and Paravalvular Abscess in a 42-Year-Old Male

Rahul Shil, Saikat Das — Tue, 22 Sep 2026 00:00:00 +0000

Infective endocarditis is a potentially life-threatening infection that may cause severe valvular and perivalvular complications, particularly when microbiological confirmation is not obtained. This case report describes a 42-year-old man who presented with progressive dyspnoea for one-month, intermittent fever, and haemoptysis, with New York Heart Association Class III functional limitation. Laboratory evaluation showed a C-reactive protein level of 73.893 mg/L, NT-proBNP of 7870 pg/mL, mild anaemia, and leucocytosis. Blood cultures remained negative after previous empirical antibiotic exposure. Chest radiography showed prominent bronchovascular markings, while high-resolution computed tomography demonstrated ground-glass opacities and patchy consolidation. Transthoracic and transoesophageal echocardiography identified multiple aortic valve vegetations, severe aortic regurgitation, and a paravalvular abscess with impending rupture. Empirical antimicrobial treatment was initiated with ceftriaxone and gentamicin, with vancomycin subsequently added; gentamicin was later discontinued. Supportive management included intravenous diuretics, ivabradine, oxygen supplementation, continuous positive airway pressure, electrolyte correction, and close clinical monitoring. Management was coordinated by cardiology and infectious disease specialists. Despite the severity of the structural cardiac findings, the patient demonstrated gradual clinical improvement with medical therapy, and surgery was not performed. The case highlights the diagnostic and management complexity of culture-negative infective endocarditis and the importance of timely echocardiographic assessment, appropriate empirical treatment, supportive care, and multidisciplinary evaluation.

Method Development, Validation and Estimation of Single Synthetic Drug Tafamidis by RP-HPLC and Green Analysis in API Form and Pharmaceutical Dosage Form

Husna Kanwal Qureshi, Hurria Fatima, Amtul Zaman, Hafsa Fatima, Md Abdul Rahman — Fri, 18 Sep 2026 00:00:00 +0000

For the quantitative determination of Tafamidis in bulk and pharmaceutical dosage forms, a straightforward, accurate, precise, and environmentally friendly reverse-phase high-performance liquid chromatographic (RP-HPLC) method was developed and validated. To achieve optimal chromatographic performance, several stationary-phase and mobile-phase compositions were evaluated during method development. A Develosil ODS C18 column (4.6 × 150 mm, 5 µm) with a mobile phase consisting of ethanol and phosphate buffer (20:80 v/v, pH 2.8), delivered at a flow rate of 0.8 mL/min, with detection at 235 nm, provided the optimum conditions. The method demonstrated a high theoretical plate count, good peak symmetry, and a retention time of approximately 2.26 minutes. The developed method was validated in accordance with ICH criteria. The system suitability parameters were within acceptable limits, with a %RSD of less than 2%. The method showed good linearity across the concentration range of 6–14 µg/mL, with a correlation coefficient (r) of 0.999. Precision studies demonstrated high repeatability, with %RSD values below 1%. The accuracy of the method was confirmed by percentage recoveries ranging from 100.42% to 101.20%. The limit of quantitation (LOQ) and limit of detection (LOD) were 2.9 µg/mL and 0.95 µg/mL, respectively. The assay of the commercial formulation showed 99.40% purity. Robustness studies indicated that small changes in chromatographic conditions had no discernible effect on method performance. In addition to analytical validation, the environmental impact of the method was assessed using Green Analytical Chemistry (GAC) evaluation tools, including AGREE, Analytical Eco-Scale, and GAPI. An AGREE score of 0.78 demonstrated good adherence to green analytical principles. The method achieved an Analytical Eco-Scale score of 91, indicating a good green analytical process. The GAPI assessment showed predominantly green zones with minimal environmental impact, largely owing to the use of ethanol as a green solvent, reduced solvent consumption, and the elimination of derivatisation steps. Overall, the developed RP-HPLC method is robust, reliable, and environmentally friendly, making it suitable for routine quality control analysis of Tafamidis in pharmaceutical formulations while supporting sustainable analytical chemistry principles.

Journal of Pharmaceutical Research International

A High-risk Case of Culture-negative Infective Endocarditis with Severe Aortic Regurgitation and Paravalvular Abscess in a 42-Year-Old Male

Method Development, Validation and Estimation of Single Synthetic Drug Tafamidis by RP-HPLC and Green Analysis in API Form and Pharmaceutical Dosage Form