Pantoea septica, a gram-negative bacillus typically associated with opportunistic bloodstream infections in neonatal intensive care units, rarely causes pulmonary infections in immunocompetent individuals. We present a case of a 30-year-old male with multifocal cavitary pneumonia, bilateral parapneumonic effusions, and positive blood cultures for Pantoea septica, occurring in the setting of prior ketamine abuse. The patient presented with fever, productive cough, chest pain, and worsening dyspnea, without significant medical history or immunocompromising conditions. Diagnostic evaluation revealed elevated inflammatory markers, characteristic radiographic findings, and successful treatment with intravenous antibiotics and pleural drainage. This case highlights the diagnostic challenge posed by Pantoea septica in pulmonary infections and suggests a potential link between ketamine abuse and susceptibility to uncommon pathogens, warranting further investigation into its immunomodulatory effects.

The Pantoea genus of bacteria is a group of Gram-negative rod-shaped bacteria in the Enterobacteriaceae family. It is an uncommon cause of infection in humans except in specific settings, including hospital-acquired infections and in immunocompromised patients. In this report, we describe the case of a 12-year-old girl with sickle cell disease who presented with a picture of sepsis and was found to have Pantoea species in her blood culture which was treated with antibiotics with a good response. From our literature review, risk factors were identified in the reported cases, for which further exploration is highly recommended.

(1) Background: The widespread use of MALDI-TOF coupled to mass spectrometry has improved diagnostic accuracy by identifying uncommon bacteria. Among Enterobacterales, Pantoea species have been seen to be implicated in several human infections, but their clinical and microbiological framework is currently based on a few anecdotal reports. (2) Methods: We conducted this five-year (2018-2023) single-center study aimed at investigating the prevalence and clinical and microbiological findings of Pantoea species bloodstream infections. (3) Results: Among the 4996 bloodstream infection Gram-negative isolates collected during the study period, Pantoea species accounted for 0.4% (n = 19) of isolates from 19 different patients, 5 of them being pediatric cases. Among Pantoea species isolates, P. agglomerans was the most frequently detected (45%; n = 9) followed by P. eucrina (30%; n = 6) and P. septica (15%; n = 3). Malignancy (35.7%) in adults and malignancy (40%) and cerebrovascular disease following meconium aspiration (40%) in pediatric patients as comorbidities and shivering and/or fever following parenteral infusion (36.8%) as a symptom/sign of Pantoea species bloodstream infection onset were the most frequently observed clinical features. Among adults, primary bloodstream infection was the most frequent (50%), whereas among pediatric patients, the most commonly identified sources of infection were catheter-related (40%) and the respiratory tract (40%). Overall, Pantoea species bloodstream infection isolates displayed high susceptibility to all the antibiotics except for ampicillin (63.2%), fosfomycin (73.7%), and piperacillin/tazobactam (84.2%). Targeted antibiotic treatment was prescribed as monotherapy for adults (71.4%) and combination therapy for pediatric patients (60%). The most prescribed antibiotic regimens were piperacillin/tazobactam (21.4%) in adults and meropenem- (40%) and aminoglycoside-containing (40%) antibiotics in pediatric patients. The overall 28-day all-cause mortality rate was 5.3% (n = 1). (4) Conclusions: The prevalence and 28-day mortality rate of Pantoea species bloodstream infections were low. The prescription of targeted therapy including broad-spectrum antibiotics could indicate an underestimation of the specific involvement of the Pantoea species in the onset of the disease, warranting further studies defining their pathogenic potential.

A previously healthy 50-year-old man was transferred to our hospital for evaluation of acute inflammation in his right eye after ocular trauma while using a grass mower. Slit lamp examination showed 1 mm-length full thickness corneal laceration without leakage, 4+ cells and inflammatory membrane in the anterior chamber, 10% hypopyon, posterior synechiae formation, and cataract change. Upon orbital computerized tomography, a metallic intraocular foreign body in the lens was identified. Vitrectomy, phacoemulsification, foreign body removal, anterior chamber irrigation, and intravitreal antibiotics injections of vancomycin and ceftazidime were performed. In a culture of humor from the anterior chamber grew Pantoea species. More procedures were performed, including intravitreal antibiotics injection of ceftazidime. Upon administering a course of intravenous ceftazidime, fortified ceftazidime and moxifloxacin eye drops, and oral prednisolone, the patient improved.