HIV&THE LUNG Year 4 Internal Medicine Notes OmpathStudy

HIV&THE LUNG Year 4 · Internal Medicine Collection: 4TH YEAR ALL NOTES / IMED / IMED 4.3 / MOGERE -- Slide 1 HIV and The Lung Dr. Alex Mogere Consultant physician Slide 2 Outline Stages of Untreated HIV Infection\n\nOpportunistic Infections- General Definition Risk based on CD4\n Pulmonary problems in HIV Infections Malignancies Others ‹#› ‹#› Slide 3 Stages of Untreated HIV Infection Review HIV Transmission\n2-3 wks\nAcute Retroviral Syndrome\n2-3 wks \nRecovery and Seroconversion\n2-4 wks \nAsymptomatic HIV Infection\nAvg 8 yrs to 30 years (EC), <2 years (RP)\nSymptomatic HIV/ AIDS\n1.3 yrs \nDeath ‹#› ‹#› Slide 4 In pts with AIDS, what is death usually from? ‹#› Slide 5 Opportunistic Infections Definition: An infection caused by a pathogen which does not usually cause disease in healthy hosts.The pathogen takes advantage of the opportunity to infect the host with a compromised immune system Can also be atypical presentation or more severe clinical manifestations of a disease which can also infect healthy hosts ‹#› Slide 6 How does HIV predispose to OIs? HIV infects the CD4 cells and uses them to replicate into more viruses\nCD4 cells are destroyed and replenished at a rate of 2 X 109 cells/day, eventually capacity is lost and depletion occurs Increased destruction Direct infection Apoptosis Lymphocyte turnover Decreased production Redistribution Without sufficient numbers of functioning CD4s, cellular immunity decreases, as well as interactions with humoral and cytotoxic immunity ‹#› Slide 7 What is the relationship between CD4 and OIs? ‹#› Slide 8 ‹#› Continuum of risk of OIs in relation to CD4 OIs can occur above their CD4 threshold rarely Although CD4 is the most important predictor of OI risk, increasing VL is also a risk (esp when CD4 300) Slide 9 How do we classify OIs? Microbiology Clinical presentation Level of immune deficiency ‹#› Slide 10 Classification of OIs: Microbiology Bacterial: tuberculosis, MAC, bacterial pneumonia and septicemia Fungal: candidiasis, pneumocystis jiroveci pneumonia (PCP), cryptococcosis, aspergillosis ‹#› Viral: cytomegalovirus, herpes simplex virus, varicella-zoster virus, JC virus Parasitic: toxoplasmosis, cryptosporidium, microsporidium, leishmania Slide 11 Classification: Clinical Brain: Cryptococcus, Toxoplasmosis, Lymphoma, Progressive multifocal leukoencephalopathy(PML), Cytomegalovirus (CMV), HIV-associated dementia Eye: CMV, Varicella zoster virus (VZV) Mouth: Herpes simplex virus (HSV), Candida\n Lungs: Pneumocystis jirovecii (PCP), Tuberculosis, bacterial pneumonia, fungal pneumonia Gut: Mycobacterium avium complex (MAC), CMV, Salmonella Cryptosporidium, Microsporidia Bone marrow: TB, MAC, histoplasmosis, leishmania Skin: HSV, VZV, mucocutaneous manifestations, pyogenic infections Genitals: HSV, Human papilloma virus, Candida ‹#› Slide 12 Classification: Immunosuppression CD4 500 Candida vaginitis, pulmonary TB, Streptococcus pneumoniae CD4: 200-500 Pneumococcal disease, herpes simplex virus, varicella zoster virus, pulmonary TB, Kaposi’s sarcoma, thrush CD4 <200 Pneumocystis jirovecii, miliary and extra-pulmonary TB, non-Hodgkin’s lymphoma, disseminated histoplasmosis, recurrent bacterial disease\n CD4<100 Toxoplasmosis, Cryptococcosis, chronic cryptosporidiosis, microsporidiosis, candidal eosophagitis CD4<50 Cytomegalovirus (CMV), Mycobacterium avium complex (MAC), CNS lymphoma, Progressive multifocal leukoencephalopathy (PML). ‹#› Slide 13 Pulmonary OIs Common Pulmonary OIs in Developing world Bacterial pneumonia – Lobar pneumoina Pneumocystis jirovecii pneumonia Tuberculosis Kaposi Sarcoma Uncommon Pulmonary OIs Histoplasmosis Penicillium Coccidiomycosis Mycobacterium Avium ‹#› Slide 14 Pneumocystis jiroveci pneumonia (PCP) ‹#› Causative organism\nFungus (NOT a protozoa) Caused by P jiroveci (formerly P carinii- rodents) Ubiquitous in the environment Initial infection usually occurs in early childhood PCP may result from reactivation or new exposure In immunosuppressed patients, possible airborne spread Prior to ART Occurred in 70-80% of patients with AIDS Treated cases with mortality of 20-40% with AIDS 90% of cases among patients with CD4<200 Slide 15 PCP Risk Factors ‹#› ‹#› Risk factors: CD4 count <200 cells/µL CD4% <14%\nPrior PCP\nOral thrush Recurrent bacterial pneumonia Unintentional weight loss High HIV RNA Slide 16 Clinical Manifestations Progressive exertional dyspnea, fever (can be predominant symptom), nonproductive cough, chest discomfort Subacute onset, worsens over days-weeks (fulminant pneumonia is uncommon) Oxygen desaturation with exercise Chest exam may be normal (early disease), or diffuse dry rales, tachypnea, tachycardia (especially with exertion), hypoxia, fever Extrapulmonary disease seen rarely; occurs in any organ, associated with aerosolized pentamidine prophylaxis ‹#› Slide 17 Diagnosis Clinical presentation, blood tests, radiographs suggestive but not diagnostic Organism cannot be cultured Hypoxemia: characteristic, may be m