Renal vein thrombosis (RVT) is a relatively uncommon condition that is most frequently observed in individuals with nephrotic syndrome. While rare, pyelonephritis (PN) may serve as a predisposing factor for secondary RVT. In such cases, one should consider the possibility of RVT when patients fail to respond to appropriate antibiotic treatment. Typically, these patients require additional anticoagulation therapy for a duration of 3 to 6 months, with a generally favorable prognosis. In this report, we present the case of a 74-year-old female who developed RVT due to Klebsiella pneumoniae PN. Additionally, we reviewed 11 cases of PN complicated by RVT, which were documented in the PubMed database over a span of 40 years, emphasizing key elements in diagnostic and therapeutic approaches. Lastly, we elaborated upon the role of thrombo-inflammation, especially in the context of sepsis.

Intravenous methylprednisolone (IVMP) pulses, widely used for managing multiple sclerosis (MS) exacerbations, can lead to acute liver injury, presenting a diagnostic challenge in distinguishing between drug-induced autoimmune-like hepatitis (DI-ALH) and idiopathic autoimmune hepatitis (AIH). This study aimed to delineate the clinical and biochemical features of IVMP-induced liver injury, discern its etiology, and evaluate the efficacy of glucocorticoid (GC) therapy in treatment. A retrospective analysis of 13 relapsing MS patients with IVMP-induced liver injury was conducted. Liver injury was classified as hepatocellular, cholestatic, or mixed, with severity assessment guiding liver biopsy in selected cases. Causality was assessed using the Roussel Uclaf Causality Assessment Method (RUCAM) and the Simplified Diagnostic Criteria for AIH. All patients were initially monitored for a minimum of six months, with a mean follow-up period of 4.30 years. The median onset of liver injury was 37.46 days post-IVMP, with a mean peak alanine transaminase (ALT) level of 618.46 U/L. antinuclear antibody (ANA) positivity was observed in 61.53% of cases, with elevated serum immunoglobulin G (IgG) at 15.38%. Hepatocellular injury was universal among patients, and causality assessment predominantly supported DI-ALH. GC therapy was administered in six cases, achieving favorable outcomes in all but one, which necessitated rituximab. Biochemical normalization occurred within a mean of 55.41 days, with GC-treated patients recovering faster (48 days). These findings support the hypothesis that IVMP can induce hepatocellular injury, likely DI-ALH, during MS exacerbations. A tapering GC regimen proved effective in promoting recovery, particularly in severe cases. Additionally, this study introduced a diagnostic and therapeutic algorithm for managing IVMP-induced liver injury, offering a practical framework for clinical application.