Brevundimonasdiminuta is a rare cause of neonatal sepsis with significant morbidity and mortality and has extensive resistance to several antibiotics leaving few options for antimicrobial therapy. Only one case has been reported in neonates till date. We report a second case of Brevundimonasdiminuta sepsis in a preterm neonate. Brevundimonas species are aerobic Gram-negative, oxidase and catalase positive, nonfermenting rods 1 to 4 mm in length and 0.5 mm in width, belonging to the Alphaproteobacteria class and Caulobacteraceae family with a DNA G + C content of 65% to 68% [1]. Infections caused by Brevundimonas species are rare in humans and are mainly nosocomial bacteremia in immunocompromised patients [2]. B. vesicularis, B. nasdae and B. diminuta are the three species isolated from human infections, while the other 29 species have not yet been isolated in humans until now [3]. Only a few clinical cases of serious opportunistic infections, particularly in patients with compromised immunity, have been reported for B. diminuta [4]. All known species of Brevundimonas spp. show a strong resistance to most antibiotics used; but according to the Centers for Disease Control and Prevention (CDC), B. vesicularis would be uniformly susceptible to aminoglycosides and anti-pseudomonal penicillins but would be resistant to ampicillin and cephalosporins [5]. B. diminuta is ubiquitous, with worldwide distribution, isolated from several sites including water, soil and plants. It is also described that it survives in disinfectants [6]. In the literature, B. diminuta is reported in humans mainly in cancer patients. These infections are mainly bacteremia, intravascular catheter infections, urinary tract infections, pleural damage (a case of empyema) and keratitis secondary to wearing visibly contaminated lenses [7–10]. To the best of our knowledge, we describe the Second reported clinical case of B. diminuta infection in a preterm neonate at Bedi Hospital, Chandigarh, India.

Brevundimonasdiminuta is a rare cause of neonatal sepsis with significant morbidity and mortality and has extensive resistance to several antibiotics leaving few options for antimicrobial therapy. Only one case has been reported in neonates till date. We report a second case of Brevundimonasdiminuta sepsis in a preterm neonate. Brevundimonas species are aerobic Gram-negative, oxidase and catalase positive, nonfermenting rods 1 to 4 mm in length and 0.5 mm in width, belonging to the Alphaproteobacteria class and Caulobacteraceae family with a DNA G + C content of 65% to 68% [1]. Infections caused by Brevundimonas species are rare in humans and are mainly nosocomial bacteremia in immunocompromised patients [2]. B. vesicularis, B. nasdae and B. diminuta are the three species isolated from human infections, while the other 29 species have not yet been isolated in humans until now [3]. Only a few clinical cases of serious opportunistic infections, particularly in patients with compromised immunity, have been reported for B. diminuta [4]. All known species of Brevundimonas spp. show a strong resistance to most antibiotics used; but according to the Centers for Disease Control and Prevention (CDC), B. vesicularis would be uniformly susceptible to aminoglycosides and anti-pseudomonal penicillins but would be resistant to ampicillin and cephalosporins [5]. B. diminuta is ubiquitous, with worldwide distribution, isolated from several sites including water, soil and plants. It is also described that it survives in disinfectants [6]. In the literature, B. diminuta is reported in humans mainly in cancer patients. These infections are mainly bacteremia, intravascular catheter infections, urinary tract infections, pleural damage (a case of empyema) and keratitis secondary to wearing visibly contaminated lenses [7–10]. To the best of our knowledge, we describe the Second reported clinical case of B. diminuta infection in a preterm neonate at Bedi Hospital, Chandigarh, India. Chief complaints: An out-born baby, delivered to a Second gravida mother at 30wk, with a birth weight of 953 g via a lower segment caesarean section (LSCS) due placenta previa, impending eclampsia, AEDF, twin pregnancy. babyhad a weak cry with secondary apnea and developed severe respiratory distress in the form of retractions and grunting with pulse oxygen saturation of 88% and was transported to our centre at HOL 2. Physical examination: On admission, the baby had severe respiratory distress with a silvermanAnderson score of 6/10, Respiratory rate: 82/min, heart rate (HR) of 162bpm, blood pressure (BP) of 50/36 mmHg and peripheral oxygen saturation (SpO2) of 76% Right upper limb. COURSE: On admission, the baby had severe respiratory with shock and was given surfactant. The child was started on ET synchronized intermittent mandatory ventilation (SIMV) mode. I.v. antibiotics Meropenem and Amikacin was started. Extubated on DOL 3 and kept on nasal CPAP and was on room air on DOL 8 and had attained full feeds. Baby had recurrent apneas on DOL 17, repeat sepsis screen was positive with CRP: TLC: Procalcitonin (PCT). Repeat blood culture showed growth of Brevundimonasdiminuta. Antibiotcs were upgraded according to the antibiogram sensitivity. The neonate required two platelet transfusion i/v/o severe thrombocytopenia. Feeds were withdrawn on DOL 17 & 18 i/v/o altered aspirates and was then was restarted. The baby responded well and Antibiotics were given for 14 days and baby was discharged. Laboratory examinations: A sepsis screen sent on admission was positive with c-reactive protein (CRP) 112 mg/L, total leucocyte count (TLC) of 22300, Platelets 30m/L, procalcitonin (PCT): 26ng/mL. Blood culture sent on admission showed growth of Brevundimonasdiminuta(Table 1). Lumbar puncture (LP) was negative for meningitis. Cefotaxime Cefexime Cefepime Ceftazidime Mero Colis Tigecy Aztreo Levo Moxi Amik S-T Intermediate Resistant Sensitive Sensitive Sensitive Resistant Sensitive Resistant Sensitive Sensitive Sensitive Sensitive Cefu: Cefuroxime; Amik: Amikacin; Gent: Gentamicin; Amp: Ampicillin; Mero: Meropenem; Cipro: Ciprofloxacin; Levo: Levofloxacin; Moxi: Moxifloxacin; Amox: Amoxicillin; S-T: Sulfamethoxazole-trimethoprim; Tigecy: Tigecycline; Aztreo: Aztreonam.

Brevundimonasdiminuta is a rare, non-fermentative, Gram-negative bacillus belonging to the family Caulobacteraceae. It is generally considered an environmental organism, frequently isolated from water sources, hospital environments, and contaminated solutions, and is only occasionally reported as a human pathogen. Its role in neonatal sepsis remains exceedingly uncommon, with only a handful of published reports worldwide. In the present case, B. diminuta was isolated from the blood culture of a 30-week, extremely low birth weight neonate who presented with late-onset sepsis (LOS) on day 17 of life. The organism demonstrated multidrug resistance with sensitivity retained to fluoroquinolones, tigecycline, amikacin, meropenem, and certain cephalosporins, consistent with the environmental acquisition profile described in literature. Neonates, particularly preterm and very low birth weight (VLBW) infants, are predisposed to infections due to immature immunity, prolonged hospitalization, invasive procedures, and exposure to broad-spectrum antibiotics. In our case, multiple factors likely contributed, including extreme prematurity, prior mechanical ventilation, and parenteral antibiotic exposure. The association of B. diminuta infection with invasive devices and prolonged NICU stay has been highlighted by other authors [8,11]. In a similar report, Han et al. [8] described a case of B. diminutabacteremia in a preterm neonate with respiratory distress syndrome, which occurred after two weeks of intensive care. The organism displayed resistance to most β-lactams and aminoglycosides but retained sensitivity to fluoroquinolones, paralleling the antimicrobial pattern seen in our case. Similarly, Sahu et al. [11] reported B. diminutasepticemia in a term neonate following intravenous fluid contamination, underscoring the organism’s environmental reservoir and potential for nosocomial spread. From an antimicrobial perspective, B. diminuta exhibits intrinsic resistance to many β-lactams and polymyxins due to low outer membrane permeability and efflux pump activity [12]. In our case, resistance to cefixime, cefotaxime, and aztreonam was observed, while meropenem, levofloxacin, and amikacin retained activity. This pattern aligns with previous sensitivity profiles reported in neonatal and adult cases [12,13]. The prompt switch to antibiotics based on culture sensitivity contributed to favorable outcomes in our patient. Interestingly, Brevundimonas infections in neonates have been associated with thrombocytopenia and elevated inflammatory markers [13], findings also observed in our case (platelets 30×10⁹/L, CRP 112 mg/L, PCT 26 ng/mL). Thrombocytopenia in such settings may be multifactorial, arising from both infection-related consumption and bone marrow suppression. Unlike other Gram-negative sepsis, B. diminuta infections are rarely associated with meningitis in neonates, and our patient’s lumbar puncture was negative. This is consistent with the series reported by Ryan et al. [14], in which bloodstream infection was the predominant presentation, with good recovery following targeted antimicrobial therapy. CASE SUMMARY: Preterm (30+3 wkr), outborn neonate presented critically ill at the time of presentation at our neonatal intensive care unit.Had features of significant respiratory distress multiorgan dysfunction at admission. Blood culture was positive for Brevundimonasdiminuta. The neonate was treated according to the antibiogram available. The neonate recovered and was subsequently discharged. OUTCOME: The baby was discharged after forty-eight, in hemodynamically stable condition on full feeds

Only one case has been reported in the newborn period with Brevundimonasdiminuta that also a case of umbilical stump infection (omphalitis).

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