Elwasila, Sammer M

Abstract Background: Clostridium ramosum ( C. ramosum ) is an anaerobic gram-positive bacillus of the human intestine and a rare cause of bacteremia. This retrospective cohort study evaluated clinical characteristics and outcomes of a multicenter cohort of adults with C. ramosum bacteremia. Methods: This multicenter retrospective cohort included adults (≥ 18 years) with true C. ramosum bacteremia at Mayo Clinic hospitals in Arizona, Florida, Minnesota, and Wisconsin from September 1, 2012, through December 31, 2025. Data were collected through search for C. ramosum in microbiological culture records. Clinical characteristics assessed included immune status, source of bacteremia, presence of sepsis, neutropenic fever, monomicrobial vs. polymicrobial bacteremia, antimicrobial resistance patterns, antimicrobial therapy, length of stay and 30-day all cause mortality. Exploratory odds ratios (ORs) with 95% confidence intervals (CIs) were reported. Results: Among 90 patients with a positive C. ramosum blood culture, 17 were classified as contaminants and 73 comprised the study cohort. Median age was 66.0 years (IQR, 56.0–75.0); 44 (60.3%) were male and 33 (45.2%) were immunocompromised (including 26 with active malignancy, while the remaining 7 were received biologic immunosuppression). The most common infection sources were gastrointestinal (32/73, 43.8%) and central line-related (8/73, 11%). At presentation, 50.7% of patients met criteria for sepsis and 15/73 (20.5%), were in septic shock. Of 73 isolates tested, 31/73 (44.3%) were clindamycin resistant and 9/73 (12.9%) tested intermediate. Anaerobic-active antimicrobial therapy was received by 53/73 (72.6%). Thirty-day mortality was 11/73 (15.1%). Mortality was 30.0% (6/20) with therapy without reliable anaerobic activity and 9.4% (5/53) with anaerobic-active antimicrobial therapy (OR, 4.02; 95% CI, 0.88–19.46; P = 0.060). The median hospital LOS was 8.0 days. Among 30-day survivors, anaerobic active antimicrobial therapy was associated with a shorter median LOS compared to therapy without reliable anaerobic activity (8.5 vs. 12.0 days). Immunocompromised patients had higher odds of monomicrobial C. ramosum bacteremia than immunocompetent patients (OR 3.16, 95% CI 1.19–8.39; p = 0.03). Patients with polymicrobial bacteremia had higher odds of sepsis (OR, 3.89; 95% CI, 1.43–10.55; P = 0.008) and septic shock (OR, 5.66; 95% CI, 1.17–27.36; P = 0.020). Patients with malignancy or neutropenia demonstrated significantly lower odds of presenting in septic shock (p = 0.018; p = 0.029 retrospectively). Microbiological clearance was achieved in 91.3% (42/46) of evaluable cases. Conclusions: This largest reported cohort defines the clinical and microbiological profile of C. ramosum bacteremia. Frequent clindamycin nonsusceptibility is clinically actionable. Several clinical associations found on univariable analysis should be further investigated in larger studies.

This is the case of a 67-year-old immunocompetent Hispanic male residing in Mexico who presented with acute right lower back and right lateral thigh pain. Initial imaging was unremarkable. He later developed painful vesicular lesions on the right foot and buttock. He was diagnosed with herpes zoster and initiated acyclovir and gabapentin. Ten days later, he developed foot drop, leg weakness, and urinary incontinence. Magnetic resonance imaging (MRI) showed enhancement of the cauda equina, and electrodiagnostic studies demonstrated right lumbar polyradiculopathy. The patient improved significantly with pain medications and physical therapy. After 8 months of physical therapy, he demonstrated significant clinical improvement. This case highlights the uncommon presentation of motor involvement in herpes zoster and emphasizes the role of imaging and electrophysiology in guiding diagnosis and management.

Background/Objectives: Non-typhoidal Salmonella (NTS) species are well-recognized causes of invasive infection in patients with sickle cell disease (SCD), with a particular predilection for the musculoskeletal system. Although Salmonella osteomyelitis is well described in this population, septic arthritis is uncommon, especially involving the shoulder joint. We describe a case of NTS bacteremia complicated by native shoulder septic arthritis in a patient with SCD and review its clinical implications. Methods: We report the clinical course, diagnostic evaluation, microbiologic findings, imaging studies, and management of a 22-year-old man with homozygous SCD who presented with a vaso-occlusive pain crisis and subsequently developed severe sepsis with persistent Salmonella enterica bacteremia following ingestion of undercooked poultry. Persistent bacteremia prompted further evaluation for metastatic infection using advanced imaging and diagnostic arthrocentesis. Results: Whole-body imaging identified septic arthritis of the native right shoulder, which was confirmed by synovial fluid cultures growing Salmonella species. The patient underwent arthroscopic irrigation and debridement for source control. Antimicrobial therapy was narrowed to intravenous ceftriaxone based on susceptibility data and continued for six weeks. The patient demonstrated clinical improvement with resolution of bacteremia and was discharged to rehabilitation to complete therapy. Conclusions: This case highlights the importance of a careful exposure history, including foodborne sources, in patients with SCD presenting with invasive Salmonella infection. Persistent bacteremia should prompt early investigation for metastatic foci, and timely surgical source control combined with targeted antimicrobial therapy is essential for optimal outcomes in this population.

Background/Objectives: Streptococcus intermedius, a member of the Streptococcus anginosus group, is characterized by a marked propensity for abscess formation but only rarely causes native-joint septic arthritis. Involvement of the acromioclavicular (AC) joint is particularly uncommon. We describe a case of native AC joint septic arthritis due to S. intermedius in a patient with multiple predisposing factors and highlight diagnostic and management considerations. Methods: We report the clinical course of a 72-year-old man with poorly controlled type 2 diabetes mellitus who presented with progressive right shoulder pain, erythema, and swelling following recurrent minor skin abrasions from a newly adopted dog. Initial management for presumed inflammatory shoulder pathology included brief systemic corticosteroids and an ultrasound-guided intra-articular ketorolac injection. Magnetic resonance imaging (MRI) was performed after symptom progression. The patient underwent operative irrigation and debridement with collection of synovial fluid and deep tissue cultures. Blood cultures and transthoracic echocardiography were obtained to evaluate for systemic involvement. Results: MRI demonstrated multiloculated periarticular abscesses and osteolysis centered on the AC joint. Operative cultures yielded high colony counts of S. intermedius from synovial fluid and deep tissues. Blood cultures and echocardiography were negative. The patient required multiple operative debridements with irrigation, adjunctive local antibiotic therapy, and prolonged targeted β-lactam treatment. Clinical and radiographic improvement was achieved following surgical source control and antimicrobial therapy. Conclusions: Native AC joint septic arthritis due to S. intermedius is rare. Older age, uncontrolled diabetes, recent intra-articular intervention, and possible zoonotic inoculation from canine wound licking may represent contributory risk factors. Early imaging, prompt surgical source control, and guideline-concordant antimicrobial therapy are essential when bone and soft tissue involvement is present.

Nocardia spp. is a Gram-positive, partially acid-fast aerobic bacterium usually associated with infection in immunocompromised people. The most common sites of infection are the skin, lungs, and the brain, however disease can disseminate and affect every organ. Clinical manifestations of cutaneous disease are varied and frequently misdiagnosed. We present a case of an immunocompetent 66-year-old man who sustained a left finger injury while gardening. He was misdiagnosed on several occasions and treated with inappropriate antibiotics against Streptococcus spp. and Staphylococcus spp. When infection spread cutaneously, sporotrichoid (lymphocutaneous) nocardiosis was suspected and the patient was started on appropriate therapy with Bactrim which resulted in a cure. We also summarize the literature on lymphocutaneous infection by Nocardia brasiliensis. By reporting this case, we want to raise awareness among clinicians about unusual causes of cellulitis, the differential diagnosis of lymphocutaneous infection and the importance of obtaining a detailed exposure history to assist in the prompt diagnosis of nocardiosis.