Acinetobacter baumannii is an important pathogen of hospital-acquired infections. Ab mainly causes respiratory tract infections, but can also cause sepsis, urinary tract infections, secondary meningitis, etc. Ab is widely distributed in the hospital environment and can survive for a long time, posing a great threat to critically ill patients and patients in the CCU and ICU, and is also referred to as ICU-acquired infections. The development of carbapenem-resistant Acinetobacter baumannii in China has been rapid, and recently “fully drug-resistant” Acinetobacter baumannii has emerged. Clinical manifestations 1, pulmonary infection In terms of the source of infection, there are both exogenous and endogenous infections. Inhalation of oropharyngeal organisms is probably the main pathogenesis of endogenous infections. Fever, cough, chest pain, shortness of breath and bloody sputum are often present. The lungs may be characterized by fine woven 7-tailed pit emaciated 3-hand pneumonia, or large lobar or lamellar infiltrative shadows, occasionally with lung abscess and exudative pleurisy manifestations. 2, wound and skin infections surgical incisions, burns and traumatic wounds, are prone to secondary inactivated bacilli skin infections, or mixed infections with other bacteria. Clinical features are not significantly different from other bacterial infections. Mostly no fever. Occasionally, it can be manifested as cellulitis. 3, genitourinary system infection Bacteroides immobilis can cause pyelonephritis, cystitis, urethritis, vaginitis, etc. It can also present asymptomatic bacteriuria, but clinically it can not be distinguished from other bacterial infections, the cause is mostly indwelling catheterization, cystostomy. 4, bacteraemia Bacteraemia is the most serious clinical type of Bacillus immobilis infection, the morbidity and mortality rate of more than 30%. Mostly secondary to other sites of infection or after intravenous catheterization, a few primary after infusion, including infusion of antibiotics, corticosteroids, anti-tumor drugs, etc.. There are fever, systemic toxicity, skin petechiae or petechiae, and hepatosplenomegaly, and in severe cases, infectious shock. A few can form plural bacteriophage bacteremia with other bacteria. 5, meningitis Meningitis mostly occurs after cranial surgery. There are manifestations of septic meningitis such as fever, headache, vomiting, neck tonicity, positive Kellogg’s sign. Laboratory:Normal or increased total white blood cell count and increased neutrophil count. Sputum specimens obtained by anti-pollution sampling techniques have greater diagnostic value. Sputum smear finding gram-negative cocci can be an important clue for diagnosis.