hiv and related gi disorders by matt johnson gastro spr

HIV and Related GI Disorders

By Matt Johnson Gastro SpR

HIV

• Lentivirus group of the Retrovirus family• 2 main types

– HIV 1 – HIV 2(confined to W. Africa)

• HIV attaches to CD4 molecules on CD4 cells (eg. Tcells) and then invades the cell. It uses reverse transcriptase to transcribe RNA to DNA, which is later incorporated into the host genome and thence replicated.

HIV Symptoms

• CDC Gp1 - Self limiting non-specific illness at 4-8/52

• CDC Gp2 - Asymptomatic infection for 10 years

• CDC Gp3 - Persistent generalised lymphadenopathy (>1cm in >2 places for >3/12)

• CDC Gp4 - Symptomatic HIV infections

HIV Symptoms

• Symptomatic HIV Infection

• a) Constitutional Symptoms (lethargy, sweats, weight loss)

• b) Haematology (pancytopenia)

• c) GI - HIV Enteropathy (N+V+D+Anorexia+Weight loss)

• d) Neuro (S+M+Auto/polyneuropathy)

• e) Dermatology (hairy oral leukoplakia)

HIV Ix and Mx

• HIV RNA titre is the best predictor of progression to AIDS and the best marker (after 3/12) of therapeutic effect

• British HIV Assoc guidelines

• When to treat– a) Symptomatic– b) HIV-1 RNA >10,000 / ml– c) CD-4 count < 500 * 106 / L

HIV Treatments

• Nucleoside Analogue Reverse Transciptase Inhibitors (NRTI’s)– Zidovudine (AZT= thymidine analogue DNA

terminator, like ddI and ddC)

– Lamivudine

• Non - NRTI’s– Nevirapine

• HIV Protease Enzyme Inhibitors– Indinavir or Saquinovir

Treatment Regimes and Aims

• <50,000 RNA = Triple Therapy• AZT + Lamivudine + Nevirapine

• >50,000 RNA = Quadruple Therapy• AZT + Lamivudine + Indinavir + Saquinavir

• HAART = Highly Active Antiretroviral Therapy

• AIM• Improve and extend life

• Decrease viral load to < 500 copies / ml after 6/12

HIV Trials

• Concorde• AZT given to asymptomatic patients with CD4 counts > 500

improved the count but with no survival benefit

• Delta 1• AZT + ddI > AZT + ddC > AZT

• Delta 2• If the patient has been on AZT for 3/12 there is added benefit

from starting ddI but not ddC• Prolongs life and delays progression

•

HIV Trials

• ACTG• Decreased vertical transmission with AZT + ddI >

AZT + ddC > AZT

• ACTG 320• Triple therapy with protease inhibitors > Dual

therapy

• Stopped early as the addition of indinavir decreased infection rate and mortalitiy by > 50%

Prophylaxis

• UK Department of Health– AZT + Lamivudine + Indinavir– Given preferably <2hr but not after >72hr– Continued for 4/52 – Reduces risk by 80%

GI Complications of HIV

• Oropharyngeal

• Oesophageal

• Constipation

• Diarrhoea

• Liver

• Abdominal Pain

• Rectal Bleeding

Oropharyngeal

• Oral Hairy Leukoplakia

• Oral Candida

• HSV type1

• Gonorrhoea

• Syphilis

• Kaposi Sarcoma

Oesophageal

• Candidiasis

• CMV

Constipation

• Chlamydia (Rectal Strictures)

• Lymphogranuloma Venereum

Diarrhoea

• Moderate– HIV Enteropathy,– Gonorrhoea– Mycobacterium spp– Giardia. Lamblia– Salmonella spp– Campylobacter spp

Diarrhoea

• Severe / Malabsorption– Cryptosporidium spp– CMV– I. Belli– Enterocytozoon bieneusi– Cyclospora spp

Diarrhoea

• Bloody– HSV– Campylobacter spp– Chlamydia trachomatis– CMV– E. histolytica– Shigella spp

Liver

• Hepatitis A,

• Hepatitis B,

• Hepatitis B+D,

• Hepatitis C

• Sclerosing Cholangitis (microsporidia)

• Drugs

Abdominal Pain

• Intestinal lymphoma

• Kaposi Sarcoma

• Mycobacterium

• CMV (gallbladder)

Rectal Bleeding

• Syphilis

• Lymphogranuloma venereum

• Kaposi Sarcoma

• Anorectal Carcinoma

• Thrombocytopenia (drug induced)

Parasites

• Protozoa• Giardia. Lamblia = Tinidazole 2g stat• E. histolytica = Metronidazole 800mg tds 5/7• Cryptosporidium = None

• Nematodes• A. Lumbricoides = Mebendazole 100mg bd3/7

• Cestodes • Taenia spp = Niclosamide 2g stat

• Lymphogranuloma Venereum• S. Japonicum = Praziquantel 25mg/kg tds 2/7

Oesophageal Candidiasis

• Most common opportunistic infection

• Nearly always C.albicans

• Retrosternal chest pain and dysphagia

• OGD with brushings or biopsies

• Differential (HSV,MAI, Neoplasia, ulcerating hairy leukoplakia)

• Oral = Fluconazole 50mg 7/7 (or 14/7)

• Oesoph/systemic = Ketocon 200mg od 14/7

CMV

• Encephalitis, Chorioretinitis, Pneumonitis,

• Oesophagitis – Severe odynophagia 20 to serpigenious ulcers

• Colitis– 10% of AIDS patients

– profuse bloody diarrhoea, LIF pain, weight loss

– fever, sb ulcers, toxic megacolon, SSC,hepatitis

• Ix = RigidSig + Bx (owls eye cyto inclusion bodies)

• Rx = Ganciclovir or Foscarnet

HSV

• Kaposi Sarcoma = HSV type 8– multifocal prolif of vascular endo (15%of gays)– haemorrhage, perforation, bile obstruction– localised/cutaneous = XRT– disseminated/visceral = Vincristine + aIFN

• Oesophagitis with severe dyspagia– OGD + Bx = multiple deep ulcers

• Proctocolitis (cellular inclusion bodies on rectal Bx)

• Acyclovir IV (5-10mg/kg tds) PO (200mg 5*/d 5/7)

Cryptosporidiosis

• Enterocyte infection causes villous fusion and increased secretions

• N + V + watery D + Anorexia• Commonly affects the biliary tree = SSC• Ix = acid fast staining cysts + oocytes• Rx = No satisfactory treatment

Spiramycin1g tds 3/52 (not available in UK)

Chlamydia

• Proctitis– similar to Crohns– Rectal Bx = Chlamydial inclusion bodies– Micro-immunoflurescent antibody tests

• Treatment– Tetracycline 500mg qds

Mycobacterium

• MAI = M. avium intracellulare• fever, night sweats, periumbilical pain, diarrhoea

• Mx = symptom relief, but eradication is difficult

• Occurs when CD4 < 200

• Rx = Rifabutin

• Prophlactic Rifabutin when CD4 < 100

• M.tuberculosis = terminal ilietis• lifelong isoniazid, treatment is non-curative

Microsporidiasis

• Diarrhoea

• Rx = Albendazole

Lymphoma

• Non Hodgkins Lymphoma (Bcell)

• fever + night sweats

• oesophagus - dysphagia and chest pain

• gastric - haematemesis

• bowel - obstruction, perforation, bleeding intussusception, altered bowel habits

• Ix = Endoscopy and fine needle biopsy

• Rx = CHOP + ABVD