Hospital-acquired bacterial pneumonia caused by susceptible Gram-negative microorganisms

What is Hospital-acquired Bacterial Pneumonia?

Hospital-acquired bacterial pneumonia (HAP), formerly known as nosocomial pneumonia, is a type of pneumonia acquired by a patient during a hospital stay and is caused by susceptible Gram-negative microorganisms. HAP is a serious complication of hospitalization and has significant implications for patient morbidity and mortality rates.

Cause of Hospital-Acquired Bacterial Pneumonia

HAP is caused by a variety of Gram-negative bacteria, including Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii, Enterobacter species, and Proteus species. These bacteria can enter the lungs through inhalation or through the bloodstream, which can be caused by aspiration of contaminated secretions.

Risk Factors of Hospital-Acquired Bacterial Pneumonia

Risk factors for HAP include prolonged hospitalization or hospital stays of over 48 hours, mechanical ventilation, immunosuppressive or corticosteroids treatment, advanced age, cancer, cirrhosis, type 2 diabetes, renal failure, and preexisting lung disease.

Symptoms of Hospital-Acquired Bacterial Pneumonia

Symptoms of HAP may include:

  • Fever
  • Chills
  • Cough
  • Production of yellow-green sputum
  • General fatigue and confusion
  • Chest pain
  • Wheezing and shortness of breath

Diagnosis of Hospital-Acquired Bacterial Pneumonia

Diagnosis of HAP can be made by collecting a sputum sample or bronchoalveolar lavage to detect the presence of Gram-negative microorganisms. Other diagnostic tests might include imaging studies such as chest x-rays and computed tomography (CT) scans of the chest.

Treatment of Hospital-Acquired Bacterial Pneumonia

Treatment of HAP usually involves antibiotics to kill the bacteria and supportive care to address any underlying medical conditions that may have contributed to the development of the infection. Hospitalization is often required for severe cases of HAP, and treatment might require mechanical ventilation, oxygen therapy, or intravenous fluids.