Infectious Diseases and Clinical Microbiology

Infectious Diseases and Clinical Microbiology is a medical specialty originating from internal medicine that deals with the diagnosis, treatment, prevention, and control of infectious diseases caused by microorganisms such as bacteria, viruses, fungi, and parasites. The rational use of antibiotic therapy, prevention of hospital-acquired infections, immunization programs, and combating emerging infectious diseases are among the core areas of activity for this department. Koru Hospital Department of Infectious Diseases and Clinical Microbiology provides effective diagnosis and treatment of infectious diseases with its expert staff and the support of a modern microbiology laboratory.

What are Infectious Diseases?

Infectious diseases are illnesses that develop as a result of the entry, multiplication, and tissue damage caused by pathogenic microorganisms in the body. These diseases can affect different parts of the body, such as the respiratory tract, gastrointestinal system, urinary system, skin and soft tissue, bone and joints, central nervous system, and bloodstream. Infectious diseases manifest in a wide clinical spectrum, ranging from mild upper respiratory tract infections to life-threatening sepsis.

Clinical microbiology is the branch of science that involves the identification of causative agents of infection in a laboratory setting, the determination of antimicrobial susceptibility, and the conduct of epidemiological surveillance studies. Infectious disease specialists make the most accurate diagnosis and treatment decisions by interpreting clinical evaluation and microbiological data together.

Commonly Encountered Infectious Diseases

Respiratory Tract Infections

Respiratory tract infections constitute the most common group of infectious diseases in the community. The main diseases in this group are as follows:

• Community-acquired pneumonia: An infection of the lung tissue that can be severe, especially in the elderly, those with chronic diseases, and immunocompromised individuals.
• Influenza (Flu): An acute infection caused by influenza viruses, characterized by sudden onset of high fever, muscle pain, fatigue, and respiratory symptoms.
• COVID-19: A disease caused by the SARS-CoV-2 virus, with a clinical presentation ranging from asymptomatic infection to severe pneumonia and multi-organ failure.
• Tuberculosis: A chronic infection caused by the Mycobacterium tuberculosis bacillus. While it primarily affects the lungs, it can also affect other organs.
• Acute bronchitis and pharyngitis: Viral or bacterial infections of the upper and lower respiratory tracts.

Urinary Tract Infections

Urinary tract infections are a group of infections that are extremely common, especially in women:

• Lower urinary tract infection (Cystitis): A bladder infection characterized by frequent urination, burning sensation, and pain in the lower abdominal region.
• Upper urinary tract infection (Pyelonephritis): A kidney infection characterized by fever, flank pain, and general malaise.
• Complicated urinary tract infections: Infections that develop on the basis of anatomical abnormalities, the presence of a catheter, or a suppressed immune system.
• Recurrent urinary tract infections: Risk factor assessment and prophylaxis strategies are planned for infections that recur more than twice a year.

Skin and Soft Tissue Infections

Skin and soft tissue infections can range from mild superficial infections to life-threatening necrotizing fasciitis:

• Cellulitis and erysipelas: Bacterial infections of the skin and subcutaneous tissue.
• Abscess: A localized infection characterized by the accumulation of pus under the skin.
• Diabetic foot infections: Serious infections that develop in diabetic patients and can lead to limb loss.
• Surgical site infections: Infections that develop in the incision area after surgery.
• Necrotizing fasciitis: A rapidly progressing and life-threatening soft tissue infection that requires emergency surgical intervention.

Bloodstream Infections and Sepsis

Sepsis is a life-threatening condition that occurs as a result of the body's dysregulated immune response to an infection and can lead to organ failure. Conditions such as bacteremia (presence of bacteria in the blood), fungemia (presence of fungi in the blood), and infective endocarditis are important diseases in this group. Early diagnosis, appropriate antibiotic therapy, and intensive care support are the fundamental components of sepsis management.

Hospital Infections and Infection Control

Hospital infections (healthcare-associated infections) are infections that are not present at the time of the patient's admission and develop at least 48 hours after admission. These infections are a significant problem in terms of patient safety, morbidity, mortality, and healthcare costs.

Activities carried out within the scope of infection control at Koru Hospital:

• Infection control committee: Determining policies for the surveillance, prevention, and control of hospital infections.
• Hand hygiene programs: Monitoring and increasing hand hygiene compliance among healthcare workers.
• Isolation precautions: Implementing contact, droplet, and airborne isolation protocols to prevent the spread of infectious diseases.
• Sterilization and disinfection: Ensuring proper sterilization and disinfection of medical devices and surfaces.
• Surveillance studies: Regular monitoring of hospital infection rates and conducting trend analyses.
• Antimicrobial resistance monitoring: Tracking and reporting antimicrobial resistance patterns throughout the hospital.

Antibiotic Stewardship (Antimicrobial Stewardship)

Rational antibiotic use is one of the most critical tasks of the infectious diseases department. Unnecessary and inappropriate antibiotic use leads to the development and spread of antimicrobial resistance, making the treatment of infections increasingly difficult.

Strategies implemented within the scope of the antibiotic stewardship program:

• Restricted antibiotic list: Use of broad-spectrum and reserve antibiotics with the approval of an infectious disease specialist.
• De-escalation: Converting broad-spectrum therapy to narrow-spectrum therapy based on culture and susceptibility results.
• Intravenous to oral switch: Converting intravenous therapy to oral therapy in patients with a suitable clinical condition.
• Optimization of treatment duration: Implementing evidence-based treatment durations and preventing unnecessarily long treatments.
• Prophylactic antibiotic protocols: Selection of appropriate antibiotics and determination of duration for surgical prophylaxis and other prophylactic indications.

Infections in Immunocompromised Patients

Immunocompromised patients include organ transplant recipients, cancer patients receiving chemotherapy, HIV/AIDS patients, individuals using long-term immunosuppressive therapy, and patients with primary immunodeficiency. In this group, various infections, including opportunistic infections, can be severe and may require strategies different from standard treatment approaches.

• Opportunistic infections: Conditions such as Pneumocystis jirovecii pneumonia, cytomegalovirus infection, invasive aspergillosis, and candidiasis.
• Prophylactic treatment: Implementation of appropriate antimicrobial prophylaxis protocols according to the risk level.
• Vaccination strategies: Planning appropriate vaccination programs before and after immunosuppressive therapy.

Travel Health and Tropical Infections

Travel health covers pre-travel consultation, vaccination, and prophylaxis services for international travel. Protective measures against infections such as malaria, dengue fever, typhoid, hepatitis A, and yellow fever are of great importance for individuals traveling to tropical regions.

• Pre-travel consultation: Providing information about the infection risk profile of the destination region, necessary vaccines, and prophylactic medications.
• Malaria prophylaxis: Initiating appropriate chemoprophylaxis for those traveling to malaria-endemic regions.
• Post-travel evaluation: Evaluating complaints such as fever, diarrhea, or rash after travel and investigating tropical infections.

Sexually Transmitted Infections

Sexually transmitted infections (STIs) are diseases caused by various bacteria, viruses, and parasites transmitted through sexual contact:

• HIV/AIDS: A chronic infection caused by the human immunodeficiency virus. Today, it can be controlled with effective antiretroviral therapies.
• Syphilis: A systemic infection caused by the Treponema pallidum bacterium, which is divided into stages.
• Gonorrhea and chlamydia: The most common types of bacterial sexually transmitted infections.
• Hepatitis B and C: Viral infections that affect the liver and can lead to chronic liver disease.
• Genital herpes and HPV: Viral sexually transmitted infections.

Diagnostic Methods

The laboratory methods used in the diagnosis of infectious diseases are as follows:

• Culture methods: Isolation of the causative agent from samples such as blood culture, urine culture, sputum culture, wound culture, and cerebrospinal fluid culture.
• Antimicrobial susceptibility tests: Determining which antibiotics the isolated agent is sensitive or resistant to.
• Serological tests: Detection of antibodies or antigens formed against infectious agents in the blood.
• Molecular diagnostic methods: Detection of the genetic material of agents using PCR (polymerase chain reaction) and other nucleic acid amplification tests.
• Rapid diagnostic tests: Obtaining results in a short time with antigen tests and immunochromatographic tests.
• Biomarkers: Assessing the severity of the infection with inflammation markers such as procalcitonin, CRP, and presepsin.

Adult Vaccination Programs

Adult vaccination is a highly effective method for preventing infectious diseases. Infectious disease specialists plan the appropriate vaccination program according to the individual's age, chronic diseases, and risk factors:

• Influenza (flu) vaccine: A seasonal vaccine recommended every autumn, especially for risk groups.
• Pneumococcal vaccine: Provides protection against pneumonia and invasive pneumococcal diseases.
• Hepatitis A and B vaccines: Effective protection against viral hepatitis.
• Shingles vaccine: A vaccine that reduces the risk of shingles in individuals over 50 years of age.
• COVID-19 vaccines: Protection against SARS-CoV-2 infection.
• Tetanus-diphtheria-pertussis vaccine: A vaccine for which a booster dose is recommended every 10 years.

When Should You Consult an Infectious Disease Specialist?

It is recommended that you consult an infectious disease specialist in the following situations:

• Prolonged or unexplained fever
• Recurrent infections
• Infections that do not respond to antibiotic treatment
• Suspicion of a hospital-acquired infection
• Febrile illnesses that develop after travel
• Need for HIV testing and counseling
• Follow-up of chronic hepatitis B or C
• Suspicion of infection in immunocompromised individuals
• Adult vaccination counseling
• Evaluation after an animal bite or needle stick injury

In the Koru Hospital Infectious Diseases and Clinical Microbiology department, our specialist physicians provide our patients with the most effective and safe healthcare services by applying current evidence-based approaches in the diagnosis and treatment of infectious diseases. You can apply to our outpatient clinic for all situations where you suspect an infection.