What is streptococcal infection?

Streptococcal infection refers to diseases caused by the invasion of Streptococcus bacteria into the human body, primarily leading to infectious diseases and hypersensitivity reactions.

However, not all streptococcal infections cause illness; some infected individuals may remain asymptomatic. Whether symptoms develop depends on the subtype of Streptococcus and the host's immune status.

Which department should I visit for streptococcal infection?

English name: Streptococcal infections.

Alias: Streptococcal bacteremia.

Departments: Infectious diseases, respiratory medicine, nephrology, dermatology, pediatrics, obstetrics and gynecology, or other relevant departments based on symptoms.

What causes streptococcal infection?

Streptococcus bacteria are widely distributed in nature and in the human upper respiratory tract (nasopharynx), digestive tract, skin surface, and genitourinary tract. Most are non-pathogenic normal flora, but a small portion can cause suppurative diseases, toxin-mediated diseases, or hypersensitivity reactions as opportunistic pathogens.

Infection occurs when the host's immunity declines or when local wounds are present and the number of pathogenic bacteria reaches a certain threshold, leading to corresponding clinical manifestations.

Who is at higher risk of streptococcal infection?

Susceptible populations mainly include immunocompromised individuals. Epidemiological studies show that streptococcal infections are common in the following groups:

• Individuals with diabetes or obesity;
• Patients with malignancies, HIV infection, or advanced liver/kidney disease;
• Alcoholics, those with cardiovascular disease, collagen vascular disease, or trauma;
• Elderly individuals, especially nursing home residents;
• Patients with cirrhosis, stroke, pressure ulcers, or neurogenic bladder;
• Pregnant women, fetuses, newborns, and children.

What are the main symptoms of streptococcal infection?

Clinical manifestations vary depending on the bacterial subtype, affected organ, and severity of infection. Common symptoms include:

• Skin and soft tissue infections:

Manifest as ulcers, pressure sores, cellulitis, abscesses, necrotizing fasciitis, or lymphedema.

• Respiratory infections:

Primarily pharyngitis and streptococcal pneumonia, presenting with high fever, chills, rapid breathing, muscle pain, loss of appetite, fatigue, or irritability.

• Cardiac infections:

Mainly infective endocarditis, myocarditis, or pericarditis, with symptoms like fever, palpitations, chest tightness, or severe dyspnea.

• Bone and joint infections:

Commonly cause suppurative arthritis, especially in children, featuring localized redness, swelling, heat, pain, and restricted movement, often with chills and high fever.

• Genitourinary infections:

Include cystitis, pyelonephritis, chorioamnionitis in pregnant women, or cases of epididymitis, urethritis, prostatitis, and endometritis. Symptoms may involve fever, nausea, vomiting, back pain, frequent/urgent/painful urination, or hematuria. In pregnant women, infection may cause fever, uterine tenderness, maternal/fetal tachycardia, purulent amniotic fluid, or leukocytosis.

• Systemic infections:

Streptococcal toxic shock syndrome is characterized by localized pain, high fever, hypotension, and multi-organ involvement, often leading to organ dysfunction or failure.

How is streptococcal infection diagnosed?

Diagnosis combines epidemiological risk factors, specific clinical manifestations, and laboratory tests. Tests include bacterial culture of local secretions or body fluids (e.g., throat swabs, vaginal secretions). Isolation of Streptococcus from blood, cerebrospinal fluid, or pleural fluid confirms the diagnosis.

How is streptococcal infection treated?

Patients should rest, avoid fatigue, and consume easily digestible food. Targeted antibiotic therapy is based on sensitivity testing. Penicillins are typically first-line; alternatives are used for allergic or resistant cases. Adequate dosage and duration are essential.

What is the prognosis for streptococcal infection?

Prognosis depends on immune status, bacterial strain, disease duration, severity, and treatment efficacy.

• Timely treatment generally yields good outcomes, though recurrence is possible.
• Untreated or improperly managed group A streptococcal respiratory infections may lead to rheumatic fever, arthritis, or nephritis.

How to prevent streptococcal infection?

Prevention focuses on lifestyle measures: maintaining regular sleep, avoiding overexertion, and exercising to boost immunity. Skin wounds should be promptly disinfected or debrided. Underlying conditions like diabetes, kidney disease, cancer, or HIV require active management to reduce infection risk.