Human immunodeficiency virus (HIV)

Cytomegalovirus broad target cell range

- epithelial cells - endothelial cells - fibroblasts and smooth muscle cells - macrophages and T-cells

Origin of HIV

-Likely arose from mutation of the simian immunodeficiency virus (SIV), a disease of chimps that probably switches and mutated years ago in africa -host switch caused by contact with infected blood of infected apes (consumption of wild animals) mutation of SIV in Africa (chimp virus), people hunted and butchered chimps coming into contact with mutated SIV infected blood, mutated SIV infected people and then it spread from there

Stage conversion of Toxoplasma gondii

1. Asexual cycle 2. Sexual cycle 3. Environmental

Forms of Kaposi sarcoma

1. Classic 2. Endemic African form 3. HIV-related 4. Iatrogenic

retrovirus

An RNA virus that reproduces by transcribing its RNA into DNA and then inserting the DNA into a cellular chromosome; an important class of cancer-causing viruses. -known to cause some forms of cancers; leukemias

First infection of cryptococcal meningitis in immunocompetent people is usually?

Asymptomatic

Transmission of Cytomegalovirus

BODY FLUIDS: close personal contact, sexual contact, congenital, blood borne, or organ transplant; found in secretions for months to years after infection

Cat scratch disease

Bacterial disease spread by cats -caused by Bartonella henselae Get through biting, scratching, licking wounds; 40% of cats carry at some point Affected organs: Skin cancer (bacillary angiomatosis) -diverse presentation; lesion similar to Kaposi's sarcoma, angiomatous nodules, friable vascular lesions, red papules, pedunculated lesions, deep subcutaneous masses Bacillary angiomatosis is a multifocal vascular proliferation seen in HIV+ patients that mimics kaposi, KS

What is the bacteria that causes cat scratch disease (bacillary angiomatosis)?

Bartonella henselae

Main initial signs/symptoms of HIV

CAN BE MILD - fever - headache - muscle aches and joint pain - skin rash - sore throat and painful mouth sores - swollen lymph nodes (mostly on NECK) - diarrhea - weight loss - cough - night sweats

What is the fungus causing Candidiasis (thrushes )?

Candida albicans

Two fungi (encapsulated yeast) that can cause lung infection and can spread to brain?

Cryptococcus neoformans & C. gatti

Candida auris

Emerging global health threat Antimicrobial resistant: Resistant to all three major classes of antifungals Can persist on surfaces and *spread between* patients -causing nosocomial infection

VERY contagious phase of HIV?

High viral load in bloodstream

Transmission of toxoplasmosis

INGESTION of: - raw or undercooked meat - food/water contaminated with oocysts - unpasteurized milk of goats/sheep (that are infected) CONGENITALLY: - mother gets it during pregnancy Blood transfusion, organ transplants

AIDS (acquired immune deficiency syndrome)

Immune system disease caused by the Human Immunodeficiency Virus (HIV) which over a period of years weakens the capacity of the immune system to fight off infection so that weight loss and weakness set in and other afflictions such as cancer or pneumonia may hasten an infected person's demise

Symptomatic HIV infection

Immune system is very weakened; appearance of opportunistic infections and are typically (often) the cause of death - fever - fatigue - swollen lymph nodes - diarrhea - weight loss - oral yeast infections (thrush) - shingles (herpes zoster) - pneumonia

When does cryptococcal meningitis become serious?

In immunocompromised people -mortality up to 12%

Toxoplasmosis in immunocompromised people

Infection of central nervous system CNS, nodules in brain and spinal cord cause seizures, cognitive impairment - nodules also in cardiac and skeletal muscles - pneumonia - eye involvement (inflammation)

Transmission of Cryptococcal meningitis

Inflation of spores -typically found in decaying wood, in soil contaminated by bird droppings

Symptoms of Cryptococcal neoformans and C. gatti infection in lungs and brain

LUNGS: - chest pain - fever - cough BRAIN - neck pain - headache - fever - nausea - vomiting - sensitivity to light - behavioral changes - coma - death

Clinical latent Infection of HIV

MOSTLY ASYMPTOMATIC -Virus still present in WHITE BLOOD CELLS - CAN LAST MANY YEARS with antiretroviral therapy

Toxoplasmosis in immunocompetent people

MOSTLY ocular disease, acute inflammatory disease of retina which worsens through repeated reactivation of parasite leading to blindness

What parasite causes toxoplasmosis?

Toxoplasma gondii - an obligate intracellular parasite

What opportunistic infection is the leading cause of death in HIV/AIDS patients?

Tuberculosis (TB)

Kaposi sarcoma (KS)

Type of cancer soft tissue cancer, caused by Kaposi herpesvirus (HHV-8) type of skin cancer often seen in patients with AIDS; consists of brownish-purple papules that begin in skin and spread to internal organs **easily confused with bacillary angiomatosis (CSD)

More at risk for AIDS?

Unprotected sex, pre-existing STD (causing genital sores), use illicit intravenous (in veins; needle)

Toxoplasmosis

a parasite which is most commonly transmitted from animals to humans by contact with contaminated feces -caused by parasite Toxoplasma gondii -Asymptomatic in MOST infected people can carry pathogen for years -Flu like symptoms -tissue cysts can form and reactivate during life -Infects many other animals (definitive host: FELIDAE) -Cat litter box, lack of hygiene after gardening, etc... -CAN CAUSE significant diseases in infants AND immunocompromised patients TRANSMISSION: INGESTION of raw meat or insufficiently cooked meat/shellfish; ingestion of food/water contaminated with oocysts; unpasteurized milk of infected goat/sheep; CONGENITAL if acquired by mother during pregnancy; BLOOD TRANSFUSION, ORGAN TRANSPLANT *infection of nucleated cells carried through body by blood or lymphatic system

Cryptococcal meningitis

an opportunistic fungal infection caused by breathing in the spores of the fungus Cryptococcus; -Cryptococcus neoformans and C. gatti are the fungi that usually infect lungs, can spread to brain TRANSMISSION: Inhalation of spores meningitis is an inflammation of the meninges, that is, the protective membranes covering the brain and spinal cord

Primary acute illness of HIV

develops sometimes 2-4 weeks AFTER the virus enters the body -FLU LIKE SYMPTOMS -weakens immune system sometimes for months/years before AIDS develops (if untreated it will result in AIDS after 8-10 years)

Common patients of candidiasis (thrush)

diabetics, immunosuppressed, asthmatics using corticoid sprays, babies

endemic african form of kaposi sarcoma

generalized with lymph node involvement occurring in CHILDREN

Iatrogenis form of kaposi sarcoma

in immunosuppressed patients also with diffuse involvement of the skin and internal organs

Tuberculosis (TB)

infectious disease caused by Mycobacterium tuberculosis; lungs usually are involved, but any organ in the body may be affected -leading cause of death in HIV/AIDS patients around the world

Opportunistic infections

infectious diseases associated with AIDS; they occur because HIV infection lowers the body's resistance and allows infection by bacteria and parasites that normally are easily contained

classic form of kaposi sarcoma

occurring in elderly men of Mediterranean and Eastern European descent on lower extremities; lesions over the lower legs of older men

HIV-related of kaposi sarcoma

occurring in patients NOT taking highly ACTIVE ANTIRETROVIRAL therapy for (HAART) with diffuse involvement of the skin and internal organs

What is often one of the first signs of HIV infection?

swollen lymph nodes

What virus causes AIDS?

HIV - Human immunodeficiency virus

human immunodeficiency virus (HIV)

A retrovirus -Infects and destroys CD4+ T cells (T helper cells, lymphocytes which stimulate the immune response of other T and B lymphocytes

Cancers subject to opportunistic infection

1. Kaposi sarcoma 2. Aggressive B-cell non-Hodgkin lymphoma 3. Cervical cancer

Opportunistic infections in HIV and in the immunocompromised

1. Pneumocystosis 2. Tuberculosis, TB 3. Candidiasis (thrush) 4. Cytomegalovirus (CMV) - Herpesvirales 5. Cryptococcal meningitis (Cryptococcus neoformans & C. gatti) 6. Toxoplasmosis 7. Cat scratch disease (bacillary angiomatosis)

Transmission of AIDS

1. Venereal (sexually) 2. Syringe sharing 3. Blood transfusions, organ transplants 4. Transplacental (during childbirth and breastfeeding)

Cytomegalovirus (CMV)

A Herpesvirales -immunocompetent deal with it easily TRANSMISSION: Body fluids; Congenital transmission **associated with serious problems in babies** (microcephaly, hearing/vision loss, seizures) MOST children contracted by age 5, half of adults by age 40 Frequent in infant facilities DNA virus that accounts for many respiratory, ophthalmic, and liver infections People carry CMV for life (asymptomatic), can be reactivated - fever - sore throat - fatigue - swollen lymph nodes

Where is cytomegalovirus found mostly?

Facilities with infants

Definitive hosts of toxoplasmosis

Felidae (CATS)

What herpesvirus causes Kaposi Sarcoma?

HHV-8

HIV prevelance

More than 5% of the population in South Africa; MOST PREVELANCE DUE TO CULTURAL PRACTICES HIGH in male-to-male sexual contact Heterosexual Drug use

What is the bacteria causing tuberculosis (TB)?

Mycobacterium tuberculosis

AIDS treatment?

NO CURE -heavy medication -prevention and control -antiretroviral drugs suppressing the replication -pre-exposure prophylaxis (PrEP) -self testing antibody detection

Candidiasis (Thrush)

Opportunistic infection caused by a fungus, CANDIDA ALBICANS (a commensal yeast that lives normally on human bodies) -Can cause symptomatic infections AFTER antibiotic treatments. Frequent in diabetics and immunosuppressed people, in asthmatics using corticoid sprays, in babies -Signs/SYMPTOMS: Inflammation and white coating of tongue, mouth, throat, oesophagus, and vagina fungus, d/t birthing process, abx, inhaled steroids s/s: white patches on tongue, gums, cheeks, itching. Rx: oral antifungals, mouth rinsing after steroid-KETOCONAZOLE

What is the fungus causing Pneumocystosis pneumonia?

Pneumocystis jirovecii (P. carinii)

Pneumocystosis

Pneumocystis jirovecii (initially P. carinii) pneumonia -a FUNGUS causing PCP -up to 20% of adult population carries this fungus -ASYMPTOMATIC MOSTLY -MOST people with PCP (30-40%) either have HIV/AIDS or are immunosuppressed (corticoid treatments) TRANSMISSION: Aerosol