WHO disease staging system

In resource-poor countries and communities, sometimes medical facilities and testing is unavailable, and it isn’t possible to decide the appropriate time to begin treatment on the basis of test results. The World Health Organization has developed a disease staging system for HIV infection which is not dependent on testing.

WHO disease staging system for HIV Infection and Disease in Adults and Adolescents

Clinical Stage I:

1. Asymptomatic

2. Generalized lymphadenopathy

Performance scale 1: asymptomatic, normal activity

Clinical Stage II:

3. Weight loss <10% of body weight

4. Minor mucocutaneous manifestations (seborrheic dermatitis, prurigo, fungal nail infections, recurrent oral ulcerations, angular cheilitis)

5. Herpes zoster within the last five years

6. Recurrent upper respiratory tract infections (i.e. bacterial sinusitis)

And/or performance scale 2: symptomatic, normal activity

Clinical Stage III:

7. Weight loss >10% of body weight

8. Unexplained chronic diarrhoea, >1 month

9. Unexplained prolonged fever (intermittent or constant), >1 month

10. Oral candidiasis (thrush)

11. Oral hairy leucoplakia

12. Pulmonary tuberculosis

13. Severe bacterial infections (i.e. pneumonia, pyomyositis)

And/or performance scale 3: bedridden <50% of the day during last month

Clinical Stage IV:

14. HIV wasting syndrome [i]

15. Pneumocystic carinii pneumonia

16. Toxoplasmosis of the brain

17. Cryptosporidiosis with diarrhoea >1 month

18. Cryptococcosis, extrapulmonary

19. Cytomegalovirus disease of an organ other than liver, spleen or lymph node (e.g.

 retinitis)

20. Herpes simplex virus infection, mucocutaneous (>1 month) or visceral

21. Progressive multifocal leucoencephalopathy

22. Any disseminated endemic mycosis

23. Candidiasis of esophagus, trachea, bronchi

24. Atypical mycobacteriosis, disseminated or pulmonory

25. Non-typhoid Salmonella septicemia

26. Extrapulmonary tuberculosis

27. Lymphoma

28. Kaposi's sarcoma

29. HIV encephalopathy [ii]

And/or performance scale 4: bedridden >50% of the day during last month

Footnotes:

i. HIV wasting syndrome: weight loss of >10% of body weight, plus either unexplained chronic diarrohea (>1 month) or chronic weakness and unexplained prolonged fever (>1 month).

ii. HIV encephalopathy: clinical findings of disabling cognitive and/or motor dysfunction interfering with activities of daily living, progressing over weeks to months, in the absence of a concurrent illness or condition, other than HIV infection, which could explain the findings.