Clinical progression of HIV infection

Solehah Jeffrey

0610108

Outline

1. Overview

2. Primary infection/ seroconversion

3. Clinical latency/intermediate stage

4. Acquired immunodeficiency syndrome (AIDS)

5. Summary

6. References

Overview

Overview

Start with CD4 of 1000cells/ml blood

In HIV infected persons, the CD4 count declines by about 10cells/ml blood/year initially

However, towards the end, the CD4 count declines by 30-60cells/ml blood/year

How does HIV infection progresses?

Primary infection/seroconversi

onClinical

latency/intermediate stage

AIDS

Primary infection/ seroconversion

The incubation periods is 2-4 weeks. Silent both clinically and serologically

Symptomatic in 70 %-80% of cases

Occurs 6-8 weeks after exposure

Primary infection/ seroconversion Symptoms include

Fever Arthralgia/ Myalgia Headache Photophobia Lethargy Sore throat with cervical lymphadenopathy Mucosal ulcers Occasionally –a transient faint pink

maculopapular rash.

Rash of acute HIV infection

Symptomatic recovery occurs after 1-3 weeks and recovery is usually complete

Parallel to return of CD4 count and fall in the viral load

Primary infection/ seroconversion

How does HIV infection progresses?

Primary infection/seroconversion

Clinical latency/intermediate stage

AIDS

Clinical latency/ intermediate stage

Early Immune deficiency (CD4>500)

and

Intermediate Immune Deficiency (CD4 200-500)

Early Immune deficiency (CD4>500) Prolonged asymptomatic period (8-10 years)

Active viral replication takes place within lymphoid tissue

Sustained viraemia with decline in CD4 count

Generally good immune response

Seroconversion

Early

(CD4>500)

I ntermediate

CD4 <500>200

Advanced

CD4<200

CD

4 C

EL

L C

OU

NT

500

200

100

50

PGLPolymyositisRecurrent vaginal

candidiasis

Persistent generalized lymphadenopathy (PGL)

Lymphadenopathy(<1cm) at two or more extrainguinal sites for more than 3 months in the absence of causes other than HIV infection.

Usually symmetical, firm, mobile and non-tender. May disappear with disease progression

Early Immune deficiency (CD4>500)

Signs and symptoms of immunocompromised

Risk of opportunistic infection and malignancy

Develop constitutional symptoms such as fever, weight loss, and night sweats

Skin and mucosal surfaces are first affected

Intermediate Immune Deficiency (CD4 200-500)

Seroconversion

Early(CD4>500)

I ntermediateCD4 <500>200

AdvancedCD4<200

CD

4 C

EL

L C

OU

NT

500

200

100

50

Acute primary infectionPGLPolymyositisRecurrent vaginal

candidiasis

Pulmonary tuberculosisHerpes zosterOropharyngeal candidiasisOral hairy leukoplakiaSalmonellosisKaposi’s sarcomaHIV associated ITPCervival intraepithelial neoplasia II-IIILymphoid interstitial pneumonitis(LIP)

How does HIV infection progresses?

Primary infection/seroconversion

Clinical latency/intermediate

stage

AIDS

Acquired Immunodeficiency Syndromes(AIDS) Diagnosis:

Having a CD4 count of less than 200 Serologic evidence of HIV infection One of the AIDS-defining opportunistic infections

Develops for a median of 2 years followed by death

Seroconversion

Early(CD4>500)

I ntermediateCD4 <500>200

AdvancedCD4<200

CD

4 C

EL

L C

OU

NT

500

200

100

50

Acute primary infectionPGLPolymyositisRecurrent vaginal

candidiasisPulmonary tuberculosisHerpes zosterOropharyngeal candidiasisOral hairy leukoplakiaSalmonellosisKaposi’s sarcomaHIV associated ITPCervival intraepithelial neoplasiaII-IIILymphoid interstitial pneumonitis(LIP)

PCPChronic mucocutaneousherpes simplexChronic cryptosporidialdiarrhoeaMicrosporidiumOesophagealcandidiasisMiliary or extrapulmonarytuberculosisHIV-asociatedwastingPeripheral neuropathy

Cerebral toxoplasmosisCryptococcal meningitis

Non-Hodgkin Lymphoma

MAICMV

Acquired Immunodeficiency Syndromes(AIDS)

Summary

0

100

200

300

400

500

600

700

800

900

1000CD4

Years : mean survival ~ 10 yrs.

CD

4 c

ounts

AIDS-definingillness

Primary Infection

Clinical latency/ Intermediate stage

References

Clinical Medicine, Kumar & Clark, sixth edtion, 2005, Elsevier

Clinical microbiology, Gladwin & Trattler, second edition, 1999

THANK YOU

Symptomatic HIV infection

As viral load rises, the CD4 count falls Clinical picture is a result of

Direct HIV effects Immunosuppression

Clinical consequence depends on three factors

1. The microbial exposure of the patient throughout life

2. The pathogenicity of organisms encountered3. Degree of immunosuppression of the host

What are the stages of HIV disease? The Centers for Disease Control (CDC) has a

disease classification system based on immune function and clinical status.

Each patient is classified with a number which is reflective of CD4 count, and a letter reflective of clinical status.

This provides clinical and prognostic information of the patients.

CD4 Cell Categories

(cells/mm3)

A

Asymptomatic OR Acute seroconversion illness OR PGL

B

HIV related conditions

(Not A or C)

C

AIDS Indicator Condition

> 500 A1 B1 C1

200-499 A2 B2 C2

< 200 A3 B3 C3

CDC Classification of HIV Infection

>500cells/mm3Acute primary infectionProgressive generalised lymphadenoPathy(PGL)Recurrent vaginal candidiasis

200-500 cells/mm3Pulmonary tuberculosisHerpes zosterOropharyngeal candidiasisOral hairy leukoplakiaSalmonellosisKaposi’s sarcomaHIV associated ITPCervival intraepithelial neoplasia II-IIILymphoid interstitial pneumonitis(LIP)

<200cells/mm3Pneumocystis carinii pneumoniaChronic mucocutaneous herpes simplexChronic cryptosporidial diarrhoeaMicrosporidiumOesophageal candidiasisMiliary or extrapulmonary tuberculosisHIV-asociated wastingPeripheral neuropathy

<100cells/mm3Cerebral toxoplasmosisCryptococcal meningitisNon-Hodgkin’s lymphomaPrimary cerebral lymphomaHIV-associated dementiaProgressive multifocal leucoencephalopathy

<50 cells/mm3Disseminated Mycobacterium avium intracellulare(MA!)CMV retinitis

CORRELATION BETWEEN CD4 COUNT AND HIV–ASSOCIATED DISEASES