Lzd, R, P, Rfb, E
Most TB drugs can cause hematologic disorders that may involve any blood cells (red cells, white cells, platelets). However, the TB drugs most involved are Lzd and rifamycins.
|
Severity grade in adults (a)Citation a.Adapted from NIAID Division of Microbiology and Infectious Diseases, severity scale, Nov-2007. |
Anaemia |
Neutropenia |
Thrombocytopenia |
|---|---|---|---|
|
Mild |
10.5 - 9.5 g/dl |
1500 - 1000/mm³ |
100,000 - 75,000/mm³ |
|
Moderate |
< 9.5 - 8.0 g/dl |
< 1000 - 750/mm³ |
< 75,000 - 50,000/mm³ |
|
Severe |
< 8.0 - 6.5 g/dl |
< 750 - 500/mm³ |
< 50,000 - 20,000/mm³ |
|
Life-threatening |
< 6.5 g/dl |
< 500/mm³ |
< 20,000/mm³ |
1) Patient on DS-TB treatment
Rifamycins can cause potentially life-threatening thrombocytopenia. This is more common when used intermittently.
Clinical features may include minor haemorrhage (e.g. epistaxis) or severe haemorrhage and thrombocytopenic purpura.
Measure platelets when thrombocytopenia is suspected:
- Moderate thrombocytopenia: stop the rifamycin and monitor platelets weekly until > 75,000/mm3.
- Severe thrombocytopenia: stop all TB drugs. Hospitalise. Treat shock or severe haemorrhage.
In any event rifamycins should not be reintroduced.
2) Patient on DR-TB treatment
Lzd may cause anaemia, neutropenia and/or thrombocytopenia.
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Toxicity |
Management |
|---|---|
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Mild to moderate
|
|
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Severe
|
|
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Life-threatening
|
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- aAdapted from NIAID Division of Microbiology and Infectious Diseases, severity scale, Nov-2007.