This bacterium is a conditional pathogen and one of the main pathogens of hospital infection. Patients with metabolic diseases, hematological diseases and malignant tumors, as well as patients after surgery or some treatments, are easy to be infected with this bacteria.

It often causes postoperative wound infection, bedsore, abscess, suppurative otitis media and so on. The infection focus caused by this bacteria can lead to blood transmission, leading to bacteremia and septicemia. Infection with Pseudomonas aeruginosa after burns can lead to death.

This kind of bacteria is everywhere, especially in humid environment. Pseudomonas aeruginosa is the most common Pseudomonas in human beings. Occasionally, it can be found in normal skin around armpit and anal genital tract, but it is very rare in feces unless antibiotics are given. This kind of bacteria usually exists in the focus together with virulent bacteria, but occasionally it can also cause external tissue infection alone. Infection usually occurs in hospitals, and this kind of bacteria often exists in sinks, disinfection solutions and urine storage containers. Through medical staff, germs can be transmitted to patients, especially in burn and neonatal intensive care units. It is an important hospital pathogen.

Many infections caused by Pseudomonas aeruginosa occur in inpatients who are weak or immunocompromised. It is the second most common infectious pathogen in intensive care unit and the common cause of ventilator-associated pneumonia. In addition to hospital-acquired infection, HIV-infected people are also easily infected by this bacteria in the community. Once infected by Pseudomonas aeruginosa, there are often signs of late HIV infection.

Pseudomonas aeruginosa infection can occur in many anatomical sites, including skin, subcutaneous tissue, bone, ear, eye, urinary tract and heart valve. The infection site is related to the entry of bacteria and the susceptibility of patients. When burned, the area under the eschar can be invaded by a large number of bacteria, and then become the focus of bacteremia, which is often a fatal complication of burns.

The clinical manifestations of infection caused by this bacterium depend on the affected site. In hospitalized patients, if Pseudomonas aeruginosa and other gram-negative bacilli coexist in the oropharynx, tracheal intubation, tracheotomy or intermittent positive pressure breathing can all cause lung infection. Pseudomonas aeruginosa bronchitis is common in the late stage of cystic fibrosis, and the isolated strains have the morphological characteristics of mucinous colonies. This strain is usually isolated from the blood of burn patients with malignant tumors. Its clinical manifestations are Gram-negative septicemia, sometimes gangrenous deep pustules, which are purple-black lesions with a diameter of about 65438±0cm, central ulcer and erythema around. This lesion is most common in axillary and anal genitalia.

This bacterium is also a common pathogen of urinary tract infection, especially for patients who have undergone urinary tract surgery, patients with urinary tract obstruction or patients who have received broad-spectrum antibiotic treatment.

Otitis externa with purulent secretion, which is common in tropical climate, is the most common clinical type of Pseudomonas aeruginosa infection in ears. Patients with diabetes can have more serious malignant otitis externa, which is characterized by severe earache, often accompanied by unilateral cerebral palsy, and requires parenteral administration. Pseudomonas aeruginosa eye infection is generally manifested as corneal ulcer, which is more common after trauma, but some patients can also be infected by contact lens or lens liquid pollution. This bacterium can be found in the drainage sinus, especially after foot trauma or deep stab wound. Sewers often smell of sweat and fruit. Many of these puncture wounds will cause Pseudomonas aeruginosa cellulitis and osteomyelitis, so besides antibiotics, early surgical expansion is needed.

In rare cases, this bacteria can cause endocarditis, which usually occurs on artificial valves installed in open heart surgery or natural valves of intravenous drug users. Right endocarditis is treated by internal medicine, but in order to cure the infection involving mitral valve, aortic valve or artificial valve, the infected valve must usually be removed.