TB in HIV context in Chaaria

TB is a chronic disease caused by mycobacterium, highly infectious and can affect all parts of the body except hair and nails. 

TB is an AIDS defining illness which may be difficult to diagnose in late HIV/AIDS stages. 

The clinical presentation of TB in HIV/AID does not differ with other patients but in addition, HIV patients may have CD4 count that is not coming up.

PATTERN  OF HIV RELATED TB.

INVESTAGATIONS

• Sputum for AAFB
• CXR
• Gene expert

EARLY HIV - LATE HIV

In early HIV, AAFB is often positive, while in late HIV AAFB is often negative

In early HIV there are often cavitations at CXR, while in late HIV there are no cavitations

BASIC PRINCIPLES IN TB TREATMENT IN HIV PATIENT.

• No use of single TB drug (use combinations).
• Drug used should be based on patients weight
• DOTS (Direct observed treatment) should be done either by health personnel or by relative.
• Entire duration should be observed.
• Don’t start ART immediately to a newly co-infected patient after start of Anti- TB, because this might lead to IRIS (start ART 2-4 weeks later).
• Nevirapine should be avoided to reduce the chances of drug – drug interactions (NVP+Rifampicin) and drug – drug toxicity (Nevirapine + Isomiazid => Hepatotoxicity).

                                                                                                  

WHAT IS TB RELATED IRIS?

IRIS stands for immune reconstitution inflammatory syndrome. This is a phenomenon experienced by HIV patients recently initiated on ART in whom the reconstitution of the immune system gets exaggerated to raise inflammatory reaction. TB associated IRIS refers to IRIS that occurs in context of HIV patients with active mycobacterial infection. The exact pathophysiology can hardly be demonstrated.

RISK  FACTORS FOR IRIS.

• Multiple prior opportunistic infections.
• Very low CD4 count (<100) at the start of ART.
• Rapid raise in CD4 cell count following initiation of ART.
• Persons in more advanced HIV disease by the time you start ART (Miliary TB and EPTB).

SIGNS AND SYMPTOMS OF IRIS.

   Newly ART started patient (within two months after initiation) who develops:

• Generalized lymphadenopathy.
• Respiratory distress or other severe respiratory tract signs and symptoms.
• Abscesses which may develop in various body parts.
• Pleural effusion.
• Skeletal lesions.
• Meningitis.

MANAGEMENT OF IRIS.

• Don’t stop ART unless in the case of a life threatening condition like increased ICP (intracranial pressure) or worsening respiratory distress occur.
• Supportive management as per patient’s presentation: e.g oxygen in distress, Incision and drainage in patient with abscess.
• Use of steroids (prednisolone 20 – 70 mg/day) in patients with dyspnea and abscess.

N/B.

• 10% of TB patientS initiated on ART will develop IRIS.
• ART initiation can be delayed even up to 8 weeks after initiating anti TB.

PREVENTION OF TB IN HIV PATIENTS.

• Intensified case finding (ICF), using ICF card in all HIV patients.
• Intengration of TB services in other departments.
• Initiation of ART soonest possible.
• Isoniazid TB prevention treatment to all HIV positive patient (5mg/kg body weight).

TB DIAGNOSIS IN CHILDREN.

INTRODUCTION.

The current TB burden in children stands at around 10 – 15 % of all TB cases detected.  

TB is common in immuno-suppressed patients, hence children, who are not as immunocompetent as adults (and especially those living with TB confirmed persons) should be evaluated for TB.

TB DIAGNOSIS IN CHILDREN.

• Most investigations relevant to TB diagnosis will be impossible to conduct in children. 
•  The pediatric score chart is encouraged for diagnosis of TB in children. Please refer to a pediatrics book for the chart.
• NEW REGIMEN FOR TB TREATMENT IN CHILDREN.

  Incorporation of ethambutol at appropriate dosage (15-25mg/kg body weight) has been approved to be of more benefit to children than the anticipated side effect (optic neuritis).  Use of injectable streptomycin has been dismissed.

TB TYPE IN CHILDREN    REGIMEN

• For newly diagnosed TB give 2 RHZE/4RHE
• For severe forms of TB (TB meningitis/bones) give 2 RHZE/10RHE
• For retreatment of TB in children give 3 RHZE/5 RHE

Regardless of their HIV status all the children below 5 years should be put on prophylactic 

5 mg/kg body weight of Isoniazid for 6 months.

Once given, isoniazid will prevent latent TB to develop to full brown illness.  

It confers prophylactic action for about 18 – 36 months.

GLOSSARY

CXR: CHEST XRAY

AAFB: ALCOOL ACID FAST BACILLI

ART: ANTI-RETROVIRAL TREATMENT

EPTB: EXTRA PULMONARY TB

RHZE: RIFAMPICINE, ISONIAZIDE, PIRAZINAMIDE, ETHAMBUTOL

RHE: RIFAMPICINE, ISONIAZIDE, ETHAMBUTOL

Dr Beppe Gaido, 

Martin