Due to the challenges associated with accurately identifying Raoultella ornithinolytica as the causative agent in urinary tract infections (UTIs), coupled with limited guidance on treatment protocols, reports of similar cases still need to be made publicly available because of their increasing emergence. In this article, we present the first documented case of a UTI caused by Raoultella ornithinolytica in a patient with triple-negative breast cancer undergoing neoadjuvant chemotherapy. This case report highlights Raoultella ornithinolytica as an uncommon yet significant pathogen, particularly in immunocompromised patients. Given the bacterium\'s antibiotic resistance patterns, it emphasizes the importance of prompt, accurate identification methods and tailored treatment strategies, especially in vulnerable populations undergoing chemotherapy.

UNASSIGNED: Gordonia terrae is an opportunistic pathogen that rarely causes clinical infections. Here, we first report a case of spontaneous bacterial peritonitis in patients with hepatitis C cirrhosis caused by Gordonia terrea.
UNASSIGNED: A 71-year-old male patient was diagnosed with spontaneous bacteria peritonitis secondary to hepatitis C cirrhosis. The result of bacterial culture in ascites was positive, and the pathogenic bacteria was preliminarily identified as the Gordonia genus by matrix-assisted laser desorption ionization-time of flight mass spectrometry. After 16S rRNA sequencing analysis, it was determined to be the Gordonia terrea. Symptoms relieved after treatment with ceftazidime.
UNASSIGNED: This case indicates that the clinical infections caused by Gordonia terrea should be brought to the forefront. Accurate and rapid bacterial identification results are highly beneficial to the diagnosis and therapeutic regime.

Pantoea, a gram-negative, rod-shaped, anaerobic bacterium, is a rare cause of human disease. Pantoea species have been known to mostly cause pulmonary disease in agricultural workers as they are native to select crops and wild animal furs. However, in very few documented cases, Pantoea has been discovered as the source of nosocomial infections, usually in the setting of an immunocompromised host. This case report details the clinical course of a 62-year-old immunocompromised female with stage 3 breast cancer presenting with acute cholecystitis and bacteremia and the unexpected discovery of Pantoea in peripheral and chemotherapy port blood cultures. After appropriate management and susceptibility testing, the patient fortunately recovered with initial cefepime and eventual levofloxacin to target the Pantoea species. To our knowledge, this is the third documented case worldwide of Pantoea isolated from cholecystitis with associated bacteremia and the first documented case in North America. Of special interest, a few months after her infection, the patient was found to be free of breast cancer. Pantoea species are known to contain levan, an exopolysaccharide, that has been seen to upregulate tumor suppressor genes. This should be considered in the future management and research of Pantoea infections.

BACKGROUND: Total hip arthroplasty is indubitably a dominant elective surgery in orthopaedics, contributing to prodigious improvement in the quality of life of patients with osteoarthritis. One of the most potentially devastating complications of this operation is periprosthetic joint infection. Immunocompromised patients might be afflicted by infrequent low-virulence organisms not typically detected with conventional procedures. Consequently, employing advanced identification methods, such as the circumstantial sonication of orthopaedic implants, could be crucial to managing such cases.
METHODS: We present a peculiar case of a 72-year-old female patient suffering from a chronic periprosthetic hip infection due to Corynebacterium striatum. The pathogen was only identified after rigorous sonication of the extracted implants. The overall management of this case was immensely exacting, primarily because of the patient\'s impaired immune system, and was finally treated with two-stage revision in our Institution.
METHODS: Although copious literature exists concerning managing periprosthetic hip infections, no concrete guidelines are available for such infections in multimorbid or immunocompromised patients with rare low-virulence microorganisms. Hence, a diagnostic work-up, antibiotic treatment and appropriate revision timeline must be determined. Sonication of extracted implants could be a powerful tool in the diagnostic arsenal, as it can aid in identifying rare microbes, such as Corynebacterium spp. Pertinent antibiotic treatment based on antibiogram analysis and apposite final revision-surgery timing are the pillars for effective therapy of such infections.
CONCLUSIONS: Corynebacterium striatum has been increasingly recognized as an emerging cause of periprosthetic hip infection in the last decade. A conspicuous rise in such reports has been observed in multimorbid or immunocompromised patients after the COVID-19 pandemic. This case is the first report of Corynebacterium striatum periprosthetic hip infection diagnosed solely after the sonication of extracted implants. This paper aims to increase awareness surrounding Corynebacterium spp. prosthetic joint infections, while highlighting the fields for further apposite research.

We describe detection of the previously rarely reported gram-positive bacterium Auritidibacter ignavus in 3 cases of chronic ear infections in Germany. In all 3 cases, the patients had refractory otorrhea. Although their additional symptoms varied, all patients had an ear canal stenosis and A. ignavus detected in microbiologic swab specimens. A correct identification of A. ignavus in the clinical microbiology laboratory is hampered by the inability to identify it by using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Also, the bacterium might easily be overlooked because of its morphologic similarity to bacterial species of the resident skin flora. We conclude that a high index of suspicion is warranted to identify A. ignavus and that it should be particularly considered in patients with chronic external otitis who do not respond clinically to quinolone ear drop therapy.

Lawsonella clevelandensis is a fastidious Gram-positive, partially acid-fast, anaerobic, catalase positive bacterium that has been reported to be a rare cause of abdominal, breast, spinal, and liver abscesses. Here, three L. clevelandensis vascular graft infections (VGIs) and cardiac infections are reported.

After seawater baths in Antalya, Turkey, a 55-year-old man suffered from Shewanella algae bacteraemia. Imported/travel-related S. algae infections should be kept in mind, also in usually rather cold geographical areas, as patterns of seawater-associated bacilli infections might change due to warming of seawater caused by climate change.

Gemellsa morbillorum (G. morbillorum) is a Gram-positive facultative anaerobe and a known commensal organism of the oropharyngeal and gastrointestinal tracts. It is considered a rare cause of infections in humans. Most of the documented infections, whereas G. morbillorum has been implicated as a causative pathogen, were infective endocarditis and deep visceral abscesses. However, there are only a handful of cases in the current literature that have reported G. morbillorum as the primary organism causing necrotizing soft tissue infections. The authors presented a rare case of post-colonoscopy necrotizing perineal soft tissue infections in an elderly patient with poorly controlled diabetes mellitus and Crohn\'s disease with G. morbillorum being the culprit pathogen of this necrotizing infection. The reported case raises concerns for this commensal organism as an emerging virulent pathogen in certain high-risk patients. The authors proposed that a combination of the long-standing Crohn\'s disease and the recent colonoscopy with rectal polypectomy has predisposed the patient to G. morbillorum bacteremia with perineal sepsis in the setting of diabetic immunosuppression. Further studies are warranted to ascertain whether G. morbillorum is acquiring increased virulence that would have enabled this organism to cause novel soft tissue infections.

BACKGROUND: Cedecea neteri is a gram-negative, oxidase-negative bacillus, a rare pathogen. Few reports are emerging globally about its antimicrobial resistance pattern especially in immunocompromised individuals with comorbidities.
METHODS: In this paper, we report the first case of C. neteri causing urinary tract infection in a pregnant woman at a specialty care hospital in the Northern Emirates of Ras al Khaimah, UAE.
CONCLUSIONS: C. neteri is a rare and unusual pathogen, unlike routine gram-negative urinary tract pathogens from the family of Enterobacteriaceae and therefore may be missed or misidentified by routine laboratories using conventional microbiology identification techniques. Hence, Cedecea infections may be under-reported. Physicians and microbiology technicians must be aware of such a rare pathogen, as most of the isolates are multi-drug-resistant and require combined antibiotic treatment with beta-lactamase inhibitors and hence pose a treatment challenge especially in immunocompromised patients with comorbidities. In recent years, it has been reported as an emerging opportunistic pathogen.

Raoultella terrigena is a rarely found opportunistic pathogen that can cause healthcare-associated infections with high mortality. It is important to differentiate it from Klebsiella species.