Louisiana Research Day Program Book 2025

Case Studies: Section 2

Case Studies: Section 2

101 A RARE ORGANISM COMMAMONAS TESTOSTERONI EMERGING AS A CAUSE OF MDR UTI- A CASE REPORT

102 METATARSAL METASTASIS OF LUNG CANCER PRESENTING AS FOOT PAIN: A RARE ENTITY CASE REPORT

Ayesha Sadiq, MD; Dipesh Upreti, MD; Fnu Arti, MD; Imran Khan, MD; Navin Ramlal, MD Saint Francis Medical Centre, Monroe, Louisiana.

Dipesh Upreti, MD 1 ; David Vien Tran, DPM 2 ; Niku Thapa, MD 1 ; Nisheem Pokharel, MD 1 ; Trisandhya Sharma, MD 1 ; Navin Ramlal, MD 1 1 St. Francis Medical Center; Department of Internal Medicine, Monroe, Louisiana; 2 St. Francis Medical Center; Department of Podiatry, Monroe, Louisiana

Introduction: Commamonas testosteroni, previously known as Pseudomonas testosteroni, is a gram negative, aerobic, non-spore forming organism commonly found in waste all over the world. Since it can be isolated from soil and animal waste, it is commonly referred to as an environmental micro-organism. C. testosteroni also tends to grow well in a liquid environment so despite its low virulence, this quality has aided in its emergence as a nosocomial pathogen. Here, we present a case of C. testosteroni as a rare cause of a multi-drug-resistant urinary tract infection in an immunocompromised patient. Case Presentation: An 88-year-old male with history of chronic indwelling foley catheter and both prostate and colon cancer status post-surgical resection presented to the ER with concerns of hematuria. On arrival, he was afebrile, tachycardic and hypertensive. Physical examination was largely unremarkable. Initial labs revealed leukocytosis, thrombocytosis and anemia. Urinalysis showed blood >100 hpf, moderate leukocyte esterase and positive nitrites suggesting an acute UTI. Evaluation with CT abdomen/pelvis suggested possibly

a bladder hemorrhage versus malignancy of the urinary bladder. Patient was started on empiric IV antibiotics, however his sample had to be sent to an outside lab to isolate causative organisms as in-house testing was inconclusive. Of note, his blood culture tested positive for Candida tropicalis, treated with micafungin. Final urine culture and sensitivity report revealed the detection of C. testosteroni, which was resistant to multiple antibiotics including cefepime, ceftriaxone, aztreonam and levofloxacin. Given patient’s complex background of being a nursing home resident with a history of cancer, chronic indwelling foley catheter, advanced age and chronic debility he was determined to be of immunosuppressed status and his treatment was escalated to meropenem. Serial CT evaluations revealed an enlarging prostate invading the bladder wall, acting as a nidus for facilitating bacterial growth. The patient was discharged after completing treatment with meropenem and micafungin. Discussion: C. testosteroni was initially named for its ability to grow in media containing testosterone as a carbon source. Since identification in 1975, approximately

50 cases of infections in humans have been reported. It predominantly causes community acquired infections; however, cases of isolation from hospital devices, such as IV lines, water in humidifiers. It has also been infrequently associated with bacteremia or septicemia. Most patients have some degree of immunosuppression such as chronic liver disease, malignancy, or kidney disease. The translocation of bacteria from the gastrointestinal tract plays a significant role in the pathogenesis of these infections. C. testosteroni generally responds well to antibiotics and rarely leads to death; however, instances of resistance to multiple drugs have been reported, as seen in our case. The organism is believed to exhibit an evolving pattern of multidrug resistance, particularly against commonly used beta-lactam antibiotics. We emphasize the importance of considering this rare organism as a potential cause of urinary tract infections, particularly in patients with immunosuppression. It is crucial to be aware of antibiotic susceptibility when determining treatment options.

Background: Bone is one of the most common sites of metastasis for many cancers. However, metastases to the extremities are rare, affecting only 0.007% to 0.3% of cancer patients with less than one-third involving the foot. Here we present an unusual symptom of foot pain in a patient due to metatarsal metastasis. A 75-year-old female with history of lung cancer presented with a complaint of right foot pain and swelling of several days, without prior trauma. Initial assessments by her primary care physician prompted a referral to the emergency department with a suspicion of DVT. Vital signs remained stable and on examination tenderness was noted on the dorsal aspect of the right mid foot. A lower extremities ultrasound ruled out DVT. However, further evaluation with an X-ray revealed a lytic lesion in the third metatarsal which had not been present on her previous X-ray 21 days earlier. She was not a candidate for MRI due to her automated implantable defibrillator. Therefore, the decision was made to proceed with a whole-body nuclear bone scan, which revealed abnormal activity in the metatarsals of the right foot. These findings, along with significant changes in plain X-ray films over very short intervals and no nidus for

infection, favored lung cancer metastasizing to a metatarsal bone. The foot biopsy was deferred after discussing it with the podiatrist and the patient, as the biopsy would not change the course of her management. Therefore, she was conservatively managed with analgesics and hospice care for her advanced cancer. Foot metastases signify widespread disease and poor prognosis. The presentation of foot pain in a patient with cancer may mimic an infectious process, which can then delay diagnosis and increase morbidity for the patient. The diagnosis of metastasis can generally be made with radiologic imaging and, if necessary, biopsies. When dealing with a patient who has a history of cancer, like the one described above, the physician should act quickly to recognize the alternative diagnoses and possibility of metastasis. This would reduce the time to treatment and relief of symptoms which is crucial for improving quality of life.

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117 2025 Research Recognition Day