Background: Recurrent malaria refers to repeated episodes of the disease in the same individual. Plasmodium vivax is known for its ability to relapse due to dormant liver-stage hypnozoites and poses a particular risk to travelers returning from endemic areas. Prompt diagnosis and treatment are crucial to prevent recurrences. Case Presentation: We present the case of a 41-year-old man from Romania who developed Plasmodium vivax malaria after traveling through Southeast Asia without chemoprophylaxis. He presented with fever, chills, myalgia, headache, vomiting, and abdominal pain. Clinical findings included mild jaundice and slight neurological signs. Laboratory tests showed severe thrombocytopenia, elevated bilirubin, inflammatory markers, and borderline creatinine levels. Malaria was confirmed by a rapid diagnostic test and blood smear microscopy. The patient was treated with doxycycline and atovaquone–proguanil. He improved and was discharged, but experienced two relapses, both confirmed as Plasmodium vivax by RT-PCR. Despite receiving primaquine as radical cure after the first Plasmodium vivax malaria relapse, a second relapse occurred. Each episode was managed with blood-stage antimalarial therapy, leading to full clinical and biological recovery. Conclusions: Malaria rarely occurs in non-endemic areas; it should be considered in patients with compatible travel history and symptoms. Given the high relapse potential of Plasmodium vivax, accurate species identification is critical to guide appropriate long-term management.

Backgrunod/Objectives: Routine identification of common bacterial pathogens is typically efficient, utilizing standardized, cost-effective methods. However, the diagnostic process becomes significantly more complex when dealing with rare or unexpected microorganisms, especially as they can be considered colonizers in many cases. Methods: This study presents diagnostic details of an uncommon pathogen, Vibrio alginolyticus, isolated from auricular discharge in a patient with non-Hodgkin lymphoma diagnosed with persistent otitis externa and explores its identification through both conventional and modern laboratory approaches. Sequential ear discharge cultures resulted in phenotypically similar but genomically different Vibrio alginolyticus isolates. We complemented classical methods like conventional culture (on Columbia agar and CLED agar), Vitek2 Compact identification, and EUCAST disk diffusion antimicrobial susceptibility testing (following the EUCAST version 12.0 guidelines) with MALDI-TOF mass spectrometry and Illumina/Nanopore whole genome sequencing. Comparative analysis of the genomes was performed with the PeGAS pipeline, Unicycler, and 1928Diagnostics SNP analysis. Results: The Vitek2 analysis identified both isolates as V. alginolyticus with 99% confidence, and this was supported by the MALDI-TOF MS results. The first isolate (A) was fully susceptible to the antibiotics tested, while the second (B) showed resistance to ciprofloxacin. Whole genome sequencing revealed 99.23% and 98.60% nucleotide identity to the V. alginolyticus reference genome for isolates A and B, respectively, with a 99.8% match between them. Isolate B acquired a gyrA (c.1870C>T) mutation that correlates with the ciprofloxacin resistance (MIC > 0.5 mg/L). Both genomes carry hlyA (hemolysin), toxR (cholera toxin regulator), genes involved in biofilm formation (rpoN, relA, spoT, opp), luxS (motility), proA, vacB (virulence factors), and tet(34) (oxytetracycline resistance). A core genome SNP distance of <100 indicates clonal relatedness. Our integrated (phenotypic and genomic) diagnostic approach confirmed V. alginolyticus and documented host resistance evolution, with a virulence repertoire that could explain the clinical evolution. Conclusions: This case highlights the utility of molecular methods in confirming species identity, detecting resistance markers, characterizing virulence determinants, and differentiating a pathogen from a colonizer, supporting targeted clinical management.

Background and clinical significance:Pasteurella spp. are Gram-negative coccobacilli, aerobic facultatively anaerobic, belonging to the Pasteurellaceae family. In humans, they are known to cause zoonotic diseases, which usually develop after dog or cat bites, licks or scratches. Case presentation: We present the case of a 61-year-old patient, with cardiovascular comorbidities, who presented to the Orthopedics Department, 38 days after knee replacement surgery, with recurrence of pain on walking, an antalgic gait with auxiliary support, and local signs of inflammation at the level of the left knee joint. The patient admitted to owning a dog who accidentally licked the post-surgical wound. The symptoms were suggestive of a post-surgical wound infection with extension to the periprosthetic area. A purulent discharge was collected from the wound during surgical debridement and sent to the microbiological laboratory for diagnosis, where Pasteurella canis was identified using MALDI-TOF MS. Antibiotic susceptibility testing (AST) was performed according to the EUCAST guidelines and empiric antibiotic treatment was started with Cefuroxime. During his future admissions to the Orthopedics and Infectious Diseases departments, two more samples were collected, in which Pasteurella canis was isolated, along with Klebsiella oxytoca (second sample), and Klebsiella oxytoca and Pseudomonas aeruginosa (third sample). Patient evolution was favorable due to the debridement of the wound and combined antibiotic treatment, with Ceftazidime and Gentamicin. Conclusions: Infections with Pasteurella canis are rare but slowly increasing due to more and more humans owning pets. The present case underlines the importance of interdisciplinary collaborations when rare pathogens are identified.

Background/Objectives: Listeria monocytogenes is an uncommon but potentially life-threatening cause of central nervous system infection, predominantly affecting older adults and immunocompromised patients. Neurolisteriosis may present with nonspecific neurological manifestations, and the absence of classical meningeal signs may delay diagnosis. We report a case of L. monocytogenes meningoencephalitis in an elderly patient without known immunosuppression, with rapid cerebrospinal fluid (CSF) molecular testing facilitating early diagnosis and appropriate antimicrobial treatment. Case presentation: A 76-year-old man with significant cardiovascular comorbidities was admitted with a 3-day history of fever, headache, nausea, vomiting, fatigue, and gait instability. He was alert on admission, with only mild meningeal signs, and initial cranial computed tomography showed no acute intracranial abnormalities. CSF analysis revealed inflammatory changes. Empirical ceftriaxone therapy was supplemented with vancomycin, followed by the initiation of intravenous ampicillin and gentamicin after molecular identification of L. monocytogenes. The diagnosis was subsequently confirmed by CSF culture, while blood cultures remained negative. Clinical and laboratory parameters improved progressively, accompanied by marked improvement in CSF findings on follow-up examination. The patient was discharged in stable condition after 18 days of hospitalization. Conclusions: Neurolisteriosis should be considered in elderly patients presenting with fever and neurological symptoms, even in the absence of overt immunosuppression or prominent meningeal signs. This case highlights the diagnostic value of rapid CSF molecular testing, particularly when blood cultures are negative and the initial clinical presentation is nonspecific. Early recognition of L. monocytogenes infection and timely initiation of targeted antimicrobial therapy are essential to improving outcomes.