Stenotrophomonas skull base osteomyelitis presenting as necrotizing otitis externa: Unmasking by CT and MRI-case report and review

Osteomyelitis due to Stenotrophomonas maltophilia treated with trimethoprim-sulfamethoxazole monotherapy

Stenotrophomonas maltophilia is an opportunistic infection commonly encountered in various systems of the human body and has been noted to be a rare cause of osteomyelitis. This report examines a rare case of osteomyelitis of the foot caused by S. maltophilia from a poorly managed foot wound and highlights the successful treatment of this condition with trimethoprim-sulfamethoxazole monotherapy.

Community-acquired Pseudomonas aeruginosa Osteomyelitis Caused by an Injury from a Dishwasher

A 70-year-old healthy woman came to our hospital with right index finger pain and swelling after an injury incurred due to a commercial dishwasher. X-ray of the hand showed osteolysis around the distal interphalangeal joint. A further examination revealed Pseudomonas aeruginosa in the unexposed pus, so the patient was treated with a total of 10 weeks of cefepime, followed by levofloxacin and debridement twice. While this may have been a case of bacterial replacement, we should still consider P. aeruginosa infection in healthy adults when faced with an episode of waterborne injury.

Detection of Enterococcus hirae in a case of acute osteomyelitis

Enterococci are important microorganisms of the gut microbiome in many mammals and cause millions of infections annually. An increasing resistance to antibiotics has led to their emergence as superinfecting nosocomial pathogens in humans. Enterococcus hirae is rarely identified in humans. In this study, we present a case of the polymicrobial osteomyelitis involving Enterococcus hirae in a 33-year-old male patient with traumatic tibia-fibula fracture after a motor vehicle accident. He underwent a right below-the-knee amputation and antibiotics with excellent improvement. Our case study helps to confirm the unexpected presence of Enterococcus hirae in a human specimen. Further studies are needed to elucidate the clinical implications of Enterococcus hirae.

Advances in the Microbiology of Stenotrophomonas maltophilia

Stenotrophomonas maltophilia is an opportunistic pathogen of significant concern to susceptible patient populations. This pathogen can cause nosocomial and community-acquired respiratory and bloodstream infections and various other infections in humans. Sources include water, plant rhizospheres, animals, and foods. Studies of the genetic heterogeneity of S. maltophilia strains have identified several new genogroups and suggested adaptation of this pathogen to its habitats. The mechanisms used by S. maltophilia during pathogenesis continue to be uncovered and explored. S. maltophilia virulence factors include use of motility, biofilm formation, iron acquisition mechanisms, outer membrane components, protein secretion systems, extracellular enzymes, and antimicrobial resistance mechanisms. S. maltophilia is intrinsically drug resistant to an array of different antibiotics and uses a broad arsenal to protect itself against antimicrobials. Surveillance studies have recorded increases in drug resistance for S. maltophilia, prompting new strategies to be developed against this opportunist. The interactions of this environmental bacterium with other microorganisms are being elucidated. S. maltophilia and its products have applications in biotechnology, including agriculture, biocontrol, and bioremediation.

Skull Base Fungal Osteomyelitis: A Case Report and Review of the Literature

Skull base osteomyelitis (SBO) is an invasive infection refractory to therapy, closely linked with malignant otitis externa (MOE). It is characterized by a mild clinical presentation that can delay cross-sectional imaging considered as the key to revealing it. Skull base osteomyelitis typically affects elderly diabetics and immunocompromised patients (>70 years). It most commonly has an otogenic origin due to an extension of MOE. The prognosis can be very poor without the administration of adequate and timely therapy at an early disease stage. Nowadays, Pseudomonas aeruginosa remains the most common pathogen associated with SBO. Fungi are a rare cause of MOE. This report documents a rare case of otogenic SBO caused by Candida parapsilosis in a diabetic patient, with persistent otologic symptoms as clinical onset and resistance to medical treatment. Fungal MOE has more subtle symptoms and is more aggressive than its bacterial counterpart. When MOE is resistant to antibacterial drugs, this should raise the suspicion of a fungal etiology of MOE. The current guidelines do not exhaustively describe the diagnosis, antifungal drugs of choice, and optimum duration of treatment. The description of these rare clinical cases should help with the multidisciplinary management of this disease in order to optimize the diagnosis and therapeutic protocol.