An Approach to a Child with

TuberculosisAbdelaziz Y. Elzouki

Professor of PediatricsConsultant Pediatric Nephrologist

Faculty of Medicine & Medical SciencesUmm Al-Qura University

Makkah, Saudi Arabia.

TuberculosisTuberculosis TB continue to be a major health hazard especially in

developing countries. The emergence of HIV & deterioration of socioeconomic

status making difficulties to eradicate the disease. 8,000,000 new TB cases are diagnosed per year. 95% in developing countries. 3,000,000 death annually. Mycobacterium tuberculosis is an acid-fast bacillus. Aerobic, non – motile, non – sporing, forming short bacillus. Acid – fastness is attributed to high lipid content. In addition to M.tuberculosis other species can cause TB e.g.

M.ofricanum, M.bouvis.

PathogenesisPathogenesis Incubation period = 4 – 8 weeks. Tuberculi bacilli mostly acquired by inhalation of

infected droplets. Droplets lodge in alveoli, they are engulfed by

alveolar macrophages. They are draining by lymphatics to the regional

lymph node (LN). The parenchymal lesion drain lymphatics & the

involved regional LN constitute the primary complex.

PathogenesisPathogenesis During acute stage, it can disseminate to spleen, bone

marrow (BM), kidney, liver through blood. Most haematogenous spread is sub-clinical except in

immuno – comprised patients are very young infant who might develop miliary TB.

After the primary dissemination cellular immunity stimulated resulting in formation of granuloma.

The center of granuloma become necrotic & might result in caseous formation.

These granuloma have dormant bacilli which have 3 – 8% chance of reactivation during person lifetime.

PULMONARYPULMONARY – TB– TB10 – 20% of infected children have

symptomatic infection.Young infant are more susceptible.In contrast to adult, children’s disease result

from primary infection.

PULMONARYPULMONARY – TB– TB

Symptoms : Low-grade fever, cough, malaise, ↓ appetite & failure to

growth. All symptomatic children will have abnormal chest

radiograph. The most common radiological findings include hilar

lymphadenopathy, followed by segmented or lobar consolidation .

Lymphadenoapthy may result in bronchial obstruction resulting in atelectosis in or hypoaeration.

Pleural effusion in 5 – 8% & it is usually unilateral.

EXTRAPULMONARY – TBEXTRAPULMONARY – TB30% of children develop extrapulmonary –

TB.These include lymphadenopathy or

lymphadenitis skin, bone, CNS, miliary TB.

TUBERCULOUS LYMPHADENITISTUBERCULOUS LYMPHADENITIS

15 – 20% of infected children.Cervical LN are especially involved.It should be differentiated from staph &

strept.

CNS – TBCNS – TBCNS – TB is more common in children.In children, it occur mostly as meningitis,

other tuberculomas, brain abscess.

TB – MENINGITISTB – MENINGITIS2 – 5% of untreated children.Usually affect infant <1 year.Presentation is not different from other

forms of meningitis.CSF reveal mild to moderate pleocytosis

initially neutrophilic turn to lymphatic predominance later.

BONE & JOINTBONE & JOINTUsually present 1 – 2 year of the primary

disease.Affected patient have reactive tuberculin

skin test.

TB – SPONDYLITISTB – SPONDYLITISVertebral osteomyelitis is commonest

tuberculous bone disease.Usually involved the dorsal & lumber

vertebrae.Wedging of the involved vertebra is a rare

consequence resulting in kyphosis deformity (Pott’s disease).

Diagnosing by CT – scan & MRI.

TB – ARTHRITISTB – ARTHRITISRare.Knee is the most common joint involved

then the hip.Clinical manifestation: include prolonged

joint pain & swelling.

MILIARY – TBMILIARY – TBMost common in young infant (<1 year).TB seed liver, lung, meninges, & BM.Patient present with acutely ill, fever,

lethargy, hepatosplenomegaly, lymphadenopathy & respiratory distress.

PPD skin test = –ve.CXR: show bilateral miliary infiltration.

DiagnosisDiagnosisTB is one of the most difficult to diagnose.In contrast to adult, where most of

diagnosis relies on microbiological identification, diagnosis in children is mostly based on clinical & epidemiological back ground.

TUBERCULIN SKIN TESTTUBERCULIN SKIN TESTIs a skin test which elicit & delayed

hypersensitivity.Two antigen are used, purified protein

derivative (PPD) & old tuberculin (OT), both obtained from supernatant extract of M.tuberculosis.

MANTOUX TESTMANTOUX TESTPerformed by intradermal injection of PPD.There are 3 strength of PPD: 1 tuberculin unit (Tu), 5 – Tu & 250 – Tu.Recommended to use 5 – Tu unit in all

cases.

CXRCXRSuspected child should have CXR.20 –25% of child with TB will have

abnormal CXR.In majority hilar lymphadenopathy, other

lesion lung collapse &/or consolidation.Cavity are rare in child & calcification are

indication of old infection.

CULTURECULTUREGastric washing: mycobacterium organism

can be recovered in up to 40% of cases of pulmonary TB.

Gastric washing is collected early morning before the child wake up.

MOLECULAR METHODSMOLECULAR METHODSPCR is technique which amplifies the DNA

of the organism.It can be applied directly to the specimen

(sputum, BM, bronchial washing).

PROPHYLAXISPROPHYLAXISINH is recommended in all child contact

with +ve adult smear of open TB.After 3 – months PPD should be reported if

–ve INH is stopped, if +ve continue INH for 9 – months.

PREVENTION:PREVENTION: Vaccine BCG. BCG is live attenuated vaccine derived from

M.bouvis. The dose is 0.05 to 0.1 cc given intradermally in

neonate the lower dose is advised. BCG lead to ↓↓ miliary TB & TB meningitis. Side effect are rare including local lymphopathies.