Tuberculosis

S/S:

• Persistence cough 2 weeks
• Sputum occasionally blood stained
• LOA, LOW
• Fever
• SOB
• Night sweat
• Chest pain uncommon
• Consolidation, fibrosis, pleural effusion..
• erythema nodosum

S/s +ve = send for screening

Ix:

• Sputum smear AFB: 
• 3 specimen (1 in early morning)
• radiometric BACTEC for early diagnosis in smear -ve (2 weeks)
• CXR
• nodular lesion
• cavitation
• apical of upper lobe also in apical pt of lower lobe
• Mantoux test
• for screeening in asymptomatic patient only
• beware of false positive or negative
• 5 mm or more is positive in
  • HIV-positive person
  • Recent contacts of TB case
  • Persons with nodular or fibrotic changes on chest x-ray consistent with old healed TB
  • Patients with organ transplants and other immunosuppressed patients
• 10 mm or more is positive in
  • Recent arrivals (less than 5 years) from high-prevalence countries
  • Injection drug users
  • Residents and employees of high-risk congregate settings (e.g., prisons, nursing homes, hospitals, homeless shelters, etc.)
  • Mycobacteriology lab personnel
  • Persons with clinical conditions that place them at high risk (e.g., diabetes, prolonged corticosteroid therapy, leukemia, end-stage renal disease, chronic malabsorption syndromes, low body weight, etc.)
  • Children less than 4 years of age, or children and adolescents exposed to adults in high-risk categories
  • previous BCG vaccine
• 15 mm or more is positive in
  • Persons with no known risk factors for TB
  • (Note: Targeted skin testing programs should only be conducted among high-risk groups)
A tuberculin test conversion is defined as an increase of 10 mm or more within a 2-year period, regardless of age.
• False Positive (low specificity)
• BCG
• skin being touch and scratch
• previous exposure
• False Negative (anergy)
• immunocompromise (HIV, Sarcoidosis, lymphoma, miliary TB)
• ESR- f up
• PCR- for rifampicin resistance
• New serological test use purified antigen, have good specificity but low sensitivity...
• Extrapulmonary TB usually need biopsy
• presentation usually non specific depends on site, LOW, LOA, fever
• TB lymphadenitis: FNA smear, culture, cytology, biopsy
• Pleural effusion: pleurocentesis and biopsy (protein >30mg/dl, glucose<30mg/dl, lymphocyte)
• Paritoneal TB: ascites AFB
• Genito-urinary: 3 early morning urine sample, sterile pyuria, urine culture, IVU, cystoscope, u/s
• TB bone and joints: vertebra collapse, paravertebrae abscess, x ray, biopsy
• Cutaneous TB (lupus vulgaris): jelly nodule
• TB meningitis: subacute, CSF microscopic, biochem, bacteriology, CT brain for basal tuberculoma or obstructive hydrocephalus
• Pericardial TB: pericardial effusion, constrictive pericarditis, *give steroid
• Miliary TB usually immunocompromised: retina, liver, LN, marrow, CXR-reticolar- nodular shadowing, +/- liver biopsy
• C+S in Ziehl- Nelson stain or LJ medium

Screening:

• Contact of sputum positive
• HIV infection
• Immigrant
• Institutional, prison, rehab centre
• other medical fac: DM,sarcoidosis, Renal failure, prolong corticosteroid, immunosupress, malignancy

Notify!!!

1. PTB
2. PTB smear +ve
3. PTB smear -ve
4. Extrapulmonary TB
5. Pulmonary with extrapulmonary TB

Terminology

New case: never tx or anti-TB drug ,4 weeks

Cure: (smear -ve at OR 1 month prior to) completion treatment AND on at least 1 previous occasion.

Relapse: 

1. sputum +ve relapse: declare cure after full course antiTB and become sputum smear +ve
2. sputum -ve relapse: declare cure after antiTB and become active TB bacteriologically, histo, clinical, radio

Chronic: remain or become smear +ve again after complete fully surpervised tx

Treatment failure: remain or become +ve again after 5 months OR patient smear +ve b4 treatment and smear +ve after 2 month treatment

Treatment after interruption: interrupted tx for >=2 month and return with smear +ve sputum or clinical or radiological

Transferred in case: transfered from another centre

radiological classification: mild moderate advance

Management

category 1: new case

category 2: relapse, treatment failure, treatment after interruption

New PTB- 6 months

Treatment:

1st line: 

1. Rifampicin (R)
2. Isonizide (H)
3. Pyrezinamide (Z)
4. Streptomycin (S)
5. Ethambutol (E)

I) NEW CASE

Intensive (3-4 drugs) (2month daily doses)

2SHRZ

2EHRZ

2HRZ

lead to rapid sputum conversion and reduce clinical symptoms

(resistance use ethambutol)

Continuation (2-3 drugs) (4 months or extended if severe, immunocompromise and extrapulmonary)

4H^2R^2

4S^2H^2R^2

3HR

4S^3H^3R^3

use rifampicin and isoniazide, if resistance add ethambutol)

II) RELAPSE, TREATMENT FAILURE, TREATMENT AFTER INTERRUPTION

Send MTB C+S (drug regime base on sensitivity and clinical response)

No initiate std therapy

Refer chest

III) CHRONIC TB

MTB C+S (rapid culture)

Refer Chest

MONITORING PATIENT:

Treatment

Initial sputum smear +ve >>> 2 months sputum smear >>> 4 months sputum smear >>> 6 months sputum smear >>> still +ve? need check sensitivity of drugs

Compliance

Education:

1. HIV testing
2. Prolong treatment and LFT monitoring
3. Taking right medication and DOTS
4. Compliance and toxicity of drug
5. Respiratory isolation

Contact tracing CDCC

Hospitalisation:

1. Gravely ill
2. Acute disseminatied TB
3. TB CNS< pericardium, adrenal, spine
4. MDR TB
5. Default frequently, compliance suspected
6. Complication: haemoptysis, pneuthorax, empyema
7. Associated factor uncontrol DM, renal failure
8. Severe side effects
9. Need desentisation to antiTB drug
10. Social reason

Chemoprophylaxis: (isoniazide 6 month, HIV +ve patient isoniazide or rifampicin 9 months)

1. young with tuberculin conversion
2. young immigrant heaf 3-4, no prior BCG
3. asymptomatic patient found by contact tracing or screening
4. HIV with mantoux +ve or contact with TB patient

DOTS (Direct Observed Treatment, Short-course)

DRUG TOXICITY MONITORING AND MX

Monitoring drug toxicity:

• Baseline: LFT, serum billirubin, serum Cr, Blood Urea, FBC, serum uric acid (pyrazinamide), any preexisting liver ds, or liver condition- alcohol
• Report and specific ask symptoms, 2monthly f/up, routine lab monitoring

Management toxicity:

• Hepatotoxicity (chemical- LFT X5 OR symptomatic LFT X3 >>>> STOP TREATMENT)
• Rifampicin (best drug, if S/E fail to use >> poor prognosis)
• Isoniazide
• Pyrizinamide
• Peripheral neuropathy (give vit B6)
• Isoniazide 
• Renal failure, orange urine
• Rifampicin
• Liver enzyme inducer (drug-drug interaction esp in HIV pt where liver met drug >>> reduce 1/2 life)
• Rifampicin
• Thrombocytopaenia, Shock
• Rifampicin
• Visual impairment 
• Ethambutol (Eye)
• 8th CN damage
• Streptomycin
• Athralgia
• pyrazinamide (contraindication in gout)
• Agranulcytosis and B6 deficiency
• Isoniazide
• Hypersensitivity
• GI upset
• Treat symptomatically if still, can withdraw

1. Challange test 
• If rash in 1st challange, NO PROCEED, wait subside and go next drug
2. Desensitization 
• Did when unable to device suitable regime without offending drug
• slowly increase dose till therapeutic dose
3. Drug interaction
• Isoniazide
• raise antiepileptic concentration (phenytoine, carbamazepine)
• Rifampicin
• induce liver enzzyme reduce 1/2 life of drug (PI, cyclosporin, corticosteroid, OCP, oral hypoglycaemic drug, oral anticoag, phenytoin, cimetidine, theophylline, digitalis glycoside)
• reduce biliary excretion of contrast
• disturb microb assay for folic acid and B12
• Streptomycin
• other ototoxicity and nephrotoxicity drugs (aminoglycoside, amphotheracin B, cephalosporin, cyclosporin, cisplatin, frsemide)
• potentiate neuromuscular blocking effect

DOTS (directly observed treatment, short course)
Standardised short-course TB treatment rigemen for 6 months under direct observation by trained supervisor (anyone) to ensure patient take every dose.
Advantage:

• cure 95%
• wide coverage via primary care
• detection via sputum is cheap, simple
• no hospitalisation and can remain towork
• prevent drug resistance which is fatal and vry expensive to treat
• follow patient to ensure cure
• economic invesment

FDC (fixed dose combination)

Advantage:

• reduce drug resistance TB
• effective regimen more likely
• decrease medication error
• prevent shortage of certain drug by logistic
• compliance
• decrease rifampicin useage on other disease

Disadvantage:

• bioavailability not sure
• hard to adjust dose

TB in HIV patient:

1. Mantoux -ve
2. Increase reactivation TB
3. Atypical presentation
4. BCG vaccine does not prevent
5. smear -ve AFB, smear taht +ve usually contain few AFB
6. Atypical CXR (lobar or bibasal pneumonia, LN)
7. extrapulmonary and miliary TB
8. Drug interaction btw HAART and Anti-TB
9. IRIS (immune reconstitution inflammatory response) result paradoxically worsening TB
10. Isoniazide prophylaxis may be needed (not life long) with clinically monitoring
11. Respiratory  isolation test TB against 1st and 2nd line drug

MDR-TB

• mortality in 80%
• early identification (suspicious CXR, MDR TB contact not until diagnosis) 
• complete treatment (make sure patient complete all drugs)
• isolation (N95 mask, automatic closing door with -ve pressure, sputum induction in isolation room) stop isolate if >3 sputum culture -ve
• screening (frequent Tuberculin skin surveillance for health care workers