Overview of Human Infectious Diseases Lecture Slides PDF

OVERVIEW OF HUMAN INFECTIOUS DISEASES CHRISTINE JOYCE M. JAVIER, RMT, MLS(ASCPI)CM 2024 Jul 11 – 13 MICRO PARA LEC CONTENTS Introduction Infectious Diseases of the Skin Infectious Diseases of the Ears Infectious Diseases of the Eyes Infectious Di...

OVERVIEW OF HUMAN INFECTIOUS DISEASES CHRISTINE JOYCE M. JAVIER, RMT, MLS(ASCPI)CM 2024 Jul 11 – 13 MICRO PARA LEC CONTENTS Introduction Infectious Diseases of the Skin Infectious Diseases of the Ears Infectious Diseases of the Eyes Infectious Diseases of the Respiratory System Infectious Diseases of the Oral Region Infectious Diseases of the Genitourinary System Infectious Diseases of the Circulatory System Infectious Diseases of the Central Nervous System (CNS) Opportunistic Infections Emerging and Reemerging Infectious Diseases Possible Relationships between Disease States and Our Microbiome INTRODUCTION Pathogens cause two general categories of diseases: 1. Microbial intoxications 2. Infectious diseases Infectious diseases are diseases that are caused by pathogens following colonization of some body site by the pathogen. Some infectious diseases affect more than one anatomical site, and some pathogens move from one body site to another during the course of a disease. Infectious Diseases of the Skin Students should be familiar with the following terms relating to skin and infectious diseases of the skin: Epidermis and Dermis Dermatitis Sebaceous glands Folliculitis Sty (or stye) Furuncle Carbuncle Macule Papule Pustule Vesicle Infectious Diseases of the Ears General information There are three pathways for pathogens to enter the ear: 1. Via the eustachian (auditory) tube, from the throat and nasopharynx 2. Via the external ear canal 3. Via the blood or lymph Otitis media—infection of the middle ear Otitis externa—infection of the outer ear canal Infectious Diseases of the Eyes Important terms relating to the eye and infectious diseases of the eye: Conjunctiva Cornea Conjunctivitis Keratitis Keratoconjunctivitis Infectious Diseases of the Respiratory System General Information Respiratory system can be divided into two parts: 1. Upper respiratory tract (URT)—paranasal sinuses, nasopharynx, oropharynx, epiglottis, and larynx 2. Lower respiratory tract (LRT)—trachea, bronchial tubes, and alveoli of the lungs Indigenous microbiota of the URT may cause opportunistic infections of the respiratory system LRT infections are the most common cause of death from infectious diseases. TERMS TO REMEMBER: Bronchitis Bronchopneumonia Epiglottitis Laryngitis Pharyngitis Pneumonia Sinusitis Infectious Diseases of the Oral Region The oral cavity is a complex ecosystem, suitable for growth of many types of microbes. The microbiota of the mouth varies from one person to the next; consists of about 300 identified species of bacteria, both aerobes and anaerobes. TERMS TO REMEMBER: Dental caries Periodontal diseases Gingivitis Periodontitis Trench mouth Infectious Diseases of the Gastrointestinal (GI) Tract General information - Transient and resident microbes continuously enter and leave the GI tract. - Most microbes are destroyed in the stomach and duodenum. Infections of the GI Tract Having Multiple Causes - Diarrhea can have many causes (e.g., foods, drugs, viruses, bacteria, protozoa, or helminths). TERMS TO REMEMBER: Colitis Diarrhea Dysentery Enteritis Gastritis Gastroenteritis Hepatitis Infectious Diseases of the Genitourinary (GU) System Urinary Tract Infections (UTIs) UTIs can be divided into upper UTIs (infections of the kidneys and ureters) and lower UTIs (infections of the bladder, urethra, and prostate). The most common cause of cystitis and pyelonephritis is E. coli; the most common cause of urethritis is Chlamydia trachomatis. TERMS TO REMEMBER: Cystitis Nephritis Urethritis Urethritis Prostatitis Pyelonephritis. Infectious Diseases of the Genitourinary (GU) System Infections of the genital tract Terms relating to infectious diseases of the genital tract: Bartholinitis Cervicitis Endometritis Epididymitis Vaginitis Vulvovaginitis Pelvic inflammatory disease (PID) Sexually transmitted diseases of the genital tract Sexually transmitted diseases (STDs) include any of the infections transmitted by sexual activities. Sometimes include diseases of not only the genital and urinary tracts, but other areas of the body as well (e.g., skin, mucous membranes) Infectious Diseases of the Circulatory System The circulatory system consists of the cardiovascular system (the heart and various vessels) and the lymphatic system (lymphatic vessels, lymphoid tissue, and lymph). Terms relating to infectious diseases of the cardiovascular system: Endocarditis Myocarditis Pericarditis. Terms relating to the infectious diseases of the lymphatic system: Lymphadenitis Lymphadenopathy Lymphangitis. Infectious Diseases of the Central Nervous System (CNS) General information The nervous system is composed of the CNS (brain and spinal cord and three membranes) and the peripheral nervous system (nerves that branch from the brain and spinal cord). There is no indigenous microbiota of the nervous system. Terms relating to infectious diseases of the CNS: Encephalitis Encephalomyelitis Meningitis Meningo-encephalitis Myelitis. Infections of the CNS Having Multiple Causes Meningitis—inflammation of the meninges Many causes, including the ingestion of poisons, ingestion or injection of drugs, reaction to a vaccine or a pathogen (e.g., a virus, a bacterium, a fungus, or a protozoan) Three major causes of bacterial meningitis: Haemophilus influenzae Neisseria meningitidis Streptococcus pneumoniae Opportunistic Infections Opportunistic pathogens (opportunists) are microbes that usually do not cause disease but have the potential to cause disease under certain conditions. Common opportunistic infections: Aspergillosis and other mold infections Candidiasis Cytomegalovirus (CMV) and herpes simplex infections Tuberculosis, malaria, and toxoplasmosis Mycobacterium avium and Pneumocystis infections Examples of Emerging Infections H1N1 (swine flu) Avian influenza (bird flu) Cryptosporidiosis Hemolytic uremic syndrome and other E. coli O157 infections Ebola hemorrhagic fever Hantavirus pulmonary syndrome (HPS) HIV infection and AIDS Human monkeypox Lassa fever Legionellosis Lyme disease Marburg hemorrhagic fever Severe acute respiratory syndrome (SARS) Examples of Reemerging Infections Cholera Dengue fever Diphtheria Malaria Rift Valley fever Tuberculosis Yellow fever Infections caused by MRSA and other “superbugs”