Pseudomonas spp. are significant nosocomial pathogens, notably due to their multidrug resistance and association with poor outcomes in hospitalized patients. The goal of this study is to delineate the demographic, clinical, and microbiological characteristics of Pseudomonas infections at a leading tertiary care hospital in Bengaluru, providing region-specific data crucial for optimizing management.

• Design: Retrospective, hospital-based study at ESIC PGIMSR, Rajajinagar, Bengaluru
• Timeframe: Jan 2024–June 2025
• Inclusion: All patients with culture-confirmed Pseudomonas infection
• Data: Demographics, infection site, species, department, risk factors, comorbidities, outcomes, antibiotic sensitivity/resistance
• Ethics: Clearance obtained from Institutional Ethics Committee, ESIC PGIMSR. No funding received.

Table1

Of the 150 patients studied, females represented 50.67% (n=76) and males 49.33% (n=74). The age distribution is shown in Table 1, with the majority aged over 19 years.

Table2: Departmental Distribution

Table3: Species Distribution

Pseudomonas infections were distributed across Medicine (29.3%), Surgery (25.3%), Pediatrics (23.3%), and ENT (22%). P. aeruginosa accounted for 74.67% of isolates, followed by P. fluorescens and P. putida (12.67% each).

Table 4 :Site of Infection

Predominant infection sites were urinary tract (23.3%), burns (22%), wounds (20%), bloodstream infections (20%), and respiratory tract (14.7%).

Table5: Clinical Outcomes

Mortality was high at 30.67%, with 24.67% continuing treatment. Discharge and recovery together accounted for 44.67%.

Antibiotic Sensitivity

Table 6: Antibiotic sensitivity

Table 7

Table 6& 7highlights the most commonly tested antibiotics and sensitivity/resistance patterns.

“Cefepime and meropenem showed sensitivity in 8.7% of isolates. The highest resistance was observed with piperacillin–tazobactam and ciprofloxacin.”

Risk Factors & Comorbidities Table8 : Major risk factors

Table 9: Underlying conditions

Immunosuppression was noted in 24.7% of patients, ICU stay in 20%, prolonged hospitalization in 19.3%, catheter use in 18.7%, and ventilator support in 17.3%. COPD (22%), CKD (16.7%), and hypertension (16%) were common underlying comorbidities.

Statistical Associations

• Significant correlation between senior age (>60) and mortality (χ²=XX, p<0.01).
• Immunosuppressed and ICU patients had significantly higher death rates (p<0.05).
• No significant gender difference in

Our findings align with global and regional data highlighting P. aeruginosa as the predominant pathogen in hospital-acquired infections. The higher incidence among seniors and adults reflects vulnerability due to comorbidities and immune senescence. The high mortality (~31%) underscores severity, particularly in immunocompromised and ICU patients.

Antimicrobial resistance patterns signify a worrying trend of multidrug resistance, especially involving Piperacillin-Tazobactam and Carbapenems. This necessitates vigilant antibiotic stewardship programs and infection control practices.

Limitations include retrospective design and lack of molecular resistance mechanism data which could augment understanding.

The clinical burden of Pseudomonas infections in our tertiary care center is substantial, with high multidrug resistance and mortality. Targeted infection control, early diagnosis, and optimized therapy guided by susceptibility patterns are essential to improve outcomes.

Funding: None.

Conflict of Interest: None declared.

Ethical Approval: Obtained from the Institutional Ethics Committee, ESIC PGIMSR, Bengaluru.

Consent to Participate: Not applicable (retrospective study). Availability of Data and Materials: Available on request.

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