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CHILDHOOD
TUBERCULOSIS
Dr IHEJI CHUKWUNONSO

OUTLINES
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Introduction/Epidemiology
Common TB terms
Etiology
Pathogenesis
Clinical manifestations
Diagnosis
Treatment
Prevention
References

INTRODUCTION
• Tuberculosis is one of the leading infectious diseases
worldwide
• About 30% of the world’s population infected
• 8-10 million people develop the dx annually
• Over 3million of these in sub-Saharan Africa
• Incidence not known actually, but estimated 25,000 new
cases annually
• Nigeria ranked 4th among the 22 high burden countries
for TB in the world and the 1st in Africa with a 2007
estimate of 460,000 new cases occurring per year
• In 2000, WHO estimated 32,310 cases(12
...

• Relapse: A px who previously received Rx and was declared
cured or completed a full course of Rx and has once again
developed sputum smear-positive TB
• Rx failure: A smear positive px who while on Rx remained,
or became smear positive again 5 months or later after
commencement of Rx
• Return after default: A px who completed at least 4 wks of
Category 1 Rx and returned smear positive after at least 8
wks of interruption of Rx

ETIOLOGY
• There are 5 closely related mycobacteria in the M
...
tuberculosis, M
...
africanum, M
...
canetti
...
tuberculosis – Most important cause of Tb in
humans
– Non–spore-forming
– Non-motile
– Pleomorphic
– Weakly gram-positive curved rods 2-4 µm long
– Obligate aerobes
– Grow best at 37-41°C
 Hallmark of all mycobacteria is acid fastness

TRANSMISSION
• Person to person, usually by airborne mucus droplet
nuclei, particles 1-5 µm in diameter that contain M
...

– Persistent cough(± productive) of ≥2 weeks or any
duration if HIV positive
– Drenching night sweats
– Wt loss or FTT
– Anorexia
– Dypsnea
– Tachypnoea
– Rhonchi
– Bronchial breath sound
– NB: may have no chest findings!

EXTRAPULMONARY TB
• DTB
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Most common in infants and young children
Occurring 2-6months of primary infection
Results from haematogenous spread
Onset of symptoms can be explosive with a fulminant
course
Wt loss, anorexia, low grade fever
Generalized lymphadenopathy and
hepatosplenomegally
Respiratory manifestations as in PTB
Symptoms of meningitis and peritonitis in 20-40% 0f
cases

• TB MENINGITIS
– Occurs usually btwn 2 – 6months after primary
infection
– Commonest in children 6months and 4yrs
– From haematogenous spread
– Obstructing hydrocephalus
– CNs 3,6 & 7 usually affected because of common
affectation of the brain stem
– Has 3 stages:
– Stage I:
• Non specific symptoms – fever, headache, irritability,
drowsiness
• Neurological signs usually absent
• Typically lasts 1-2 wk

TB meningitis stages contd…
• Stage 2:
– Usually begins more abruptly
– Most common features:
• Lethargy, nuchal rigidity, seizures, positive meningeal signs,
hypertonia, vomiting, CN palsies, and other focal neurologic
signs
• Hydrocephalus, raised ICP, and vasculitis

• Stage 3:
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Coma
Hemiplegia or paraplegia
Hypertension, deterioration of vital signs, and
Decerebrate posturing
Eventually death
...


• CONGENITAL TB
– Rare
– Typically develop during the 2nd or 3rd week of life
– Most important clue for rapid diagnosis of congenital
tuberculosis is a maternal or family history of
tuberculosis
– Features:
• Poor feeding, poor wt gain, cough, lethergy, irritability
• Fever, ear discharge, skin lesion
• FTT, jaundice, hepatoslenomegally, tachypnoea,
lymphadenopathy

– The mortality rate of congenital tuberculosis remains
very high because of delayed diagnosis

LABORATORY DIAGNOSIS
• SCREENING TESTS
1
...
1mL of PPD intradermally at the volar aspect
Read 48 – 72 hrs; induration NOT erythema measured
Has a sensitivity and specificity of approx 90%
TST is interpreted on the basis of 3 "cut points": 5 mm, 10
mm, and 15 mm

– ≥5 mm is considered a positive in:
• Close contacts with known or suspected contagious cases
• Px with immunosuppression(eg, HIV) or on
immunosuppressive medications
• Children with abnormal CXR finding consistent with active
TB, previously active TB, or clinical evidence of the disease

– ≥10 mm considered positive in the following
children:
• Children at higher risk of dissemination, eg under 5’s,
immunosuppressed
• Children with increased exposure to the disease,(eg,
homeless, HIV infected, users of illicit drugs, residents
of nursing homes, incarcerated or institutionalized
persons);
• Children born in or whose parents were born in highprevalence areas of the world

– ≥15 mm considered positive in children aged 5
years or older without any risk factors for the
disease

2
...
g
...
TB test (T-Spot)
– Detect MTB infection but cannot distinguish latent TB from
active TB
...
N
...
signs
X-ray
feature

A score of 7 or more indicates a high likelihood of tuberculosis

TREATMENT
• The aims of TB treatment are to:
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Cure the patient of TB
Decrease transmission of TB to others
Prevent the development of acquired drug resistance
Prevent relapse
Prevent death from TB or its complications

• 1st Line – “RIPES”
• 2nd Line:
– Capreomycin, Ciprofloxacin, Cycloserine, Ethionamide,
Kanamycin, Ofloxacin, Levofloxacin, and Paraaminosalicylic acid

Rx of Susceptible Dx
DRUGS

Dose (mg/kg)

Dose Range (mg/kg) Type

Rifampicin (R)

10

8 - 12

-cidal

Isoniazide (H)

5

4-6

-cidal

Pyrazinamide (P)

25

20 - 30

-cidal

Ethambutol (E)

15

15 - 20

-static

Streptomycin (S)

15

12 - 18

-cidal

REGIMEN 1: 2(HRZE) / 4(HR)
REGIMEN 2: 2(HRZE)/ 7 (HR) - Severe or complicated
disease (meningitis, TB bones/joints, miliary TB)

Adjunctive treatment
• Pyridoxine (Vitamin B6) rarely used in
children
• Steroids for TB meningitis and pericarditis

Common side effects of Anti-Koch’s
SIDE EFFECTS

DRUG(S) RESPONSIBLE

MAJOR
Skin itching/ rash

Streptomycin, Rifampicin, Isonazid

Deafness (no wax on otoscopy)

Streptomycin

Dizziness (vertigo, nystagmus)

Streptomycin

Jaundice (other causes excluded)

Isoniazid, Rifampicin, Pyrazinamide

Vomiting, confusion

Isoniazid, Rifampicin, Pyrazinamide

Visual impairment/ loss

Ethambutol

Generalised purpura, shock and purpura

Rifampicin

MINOR
Anorexia, nausea, abdominal pains

Rifampicin

Joint pains

Pyrazinamide

Burning sensation in feet

Isoniazid

Orange/ red coloured urine

Rifampicin

Drug Resistant
• Drug resistant TB: Resistant to atleast one 1st line
drug
• MDR TB: Resistant to more than one drug and
atleast INH and RIF

• XDR TB: resistant to INH and RIF plus any
fluoroquinolone and atleast one of the three
injectable 2nd line (amikacin, kanamycin or
capreomycin)
• NB: Any of these could be 1° or 2°

• MDR TB Mgt Principles:
– At least 2 drugs to which the isolate is susceptible
should be administered
– Never add a single drug to an already failing regimen
– Resistance pattern, toxicities of the drugs, and
patients' responses to treatment determine duration
and the regimen selected
– Regimen for 18 – 24 months
– Initial Rx regimen should include 4 drugs:
• At least 2 bactericidal drugs (eg, INH, rifampin),
pyrazinamide, and either streptomycin OR
• another aminoglycoside (also bactericidal) OR
• High-dose ethambutol (25 mg/kg/d) should also be
incorporated into the regimen

NB: Any Rifampicin resistant treated as MDR TB

• XDR-TB:
– High mortality rate maybe upto 90%
– Individualize Rx
– Suggested: 4 months intensive phase (5 drugs)
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Kanamycin
Ethionamide
Pyrazinamide
Ofloxacin
Cycloserine or Ethambutol

NEONATE OF A MOTHER WITH TB
• Should be started on INH soon after delivery
• Mother’s Rx continued or commenced
• INH for baby continued until mother is sputum culture
negative thrice
• Thereafter, baby shld have a mantoux test
• If negative, INH discontinued and child vaccinated with
BCG
• If positive, CXR shld be taken to exclude TB dx
• If CXR is normal, INH continued for 9-12 months
• If radiological signs of TB dx, child shld be treated as
such with combination therapy

TB AND BCG VACCINATION
• Efficacy for adult pulmonary TB 0-80% in
randomised clinical trials
• Best efficacy against serious childhood disease
– 64% protection against TB meningitis
– 78% protection against DTB

• BCG important for young children, inadequate
as a single strategy

REFERENCES
• Nelson Textbook of Pediatrics, 19th Edition, 2011
• Paediatrics and Child Health in a Tropical Region,
2nd Edition, Jonathan C
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