Sepsis is a common and critical complication in HIV-infected patients and an important marker of high risk of patient death. The widely used diagnostic criteria for sepsis still have many deficiencies and do not allow for good prediction and timely determination of the onset of sepsis. In HIV-infected patients, abnormal activation of monocyte-macrophage is also a key mechanism in the development of their sepsis. Monocyte distribution width (MDW) is a marker of the degree of peripheral blood monocyte activation and has been recommended abroad for the early diagnosis of adult sepsis patients in emergency departments. However, in China, MDW has not been applied to the clinic yet, and the related studies are almost blank. Therefore, it is worthwhile to analyze the monocyte activation status of HIV-infected patients by MDW assay and thus predict the occurrence of sepsis.

This is a prospective observational study, and investigators intend to collect HIV-infected patients in our hospital within 1 year from the conduct of this study and hospitalized, after informed consent, for inclusion in the study. Investigators will collect clinical data, basic laboratory indicators, and test MDW levels of the patients and follow the patients until discharge or death.

Inclusion Criteria:

• Positive ELISA test results for HIV-1 antibodies;
• Hospitalized patients; Voluntarily signing the patient's informed consent and being able to promise to be followed up;
• No plans to move away from the current trial site during the course of the trial.

Exclusion Criteria:

• Western Blot and/or HIV RNA assay confirmed as HIV negative;
• Women who are pregnant or breastfeeding;
• Current drug users;
• Persons with a history of alcohol abuse that cannot be terminated;
• Persons of non-Chinese nationality;
• Other patients who, in the judgment of the investigator, are deemed unsuitable for participation in this trial.

HIV-infected patients hospitalized in our hospital within 1 year since this study was conducted.