Pulmonary TB : Dr S HarrisPulmonary TB Not an easy diagnosis By Dr S Harris Department of Paediatrics: March 2004 Recent Exam questions • 1999: – Describe how to perform read and

Department of Paediatrics: March 2004

Pulmonary TB

Not an easy diagnosis

By Dr S Harris


Recent Exam questions

• 1999:

– Describe how to perform read and interpret the mantoux test

• 1998

– Describe your mx of a newborn baby whose mother is diagnosed with pulmonary TB

– Describe your mx of an 18mo boy whose grandfather has recently died of TB

– Describe your mx of a 3 year old HIV positive child with a mantoux reading 7 mm

• 1996

– Discuss the problems of accurately diagnosing PTB in childhood

• 1989

– Discuss the diagnosis and management of tuberculosis in Children


Pulmonary Tuberculosis

• The diagnosis is often difficult in children.

– The signs and symptoms are non-specific,

– the chest X-ray is often not diagnostic and

– isolation of the organism may not be possible

• Suspicion is half-way to the diagnosis• Always ask about TB contacts


> 7 = high likelihood of TB

Angular deformity of spine

CNS signs/abn CSF

Abdominal mass or ascites

Joint or bone swelling

Lymph nodes

No response to treatment

Unexplained fever

Not improving after 4 weeks

Malnutrition

positiveTuberculin test

Proved sputum positive

Reported by family

NoneFamily hx of TB

<60%60 – 80%>80%Nutrition

>42 - 4< 2Weeks of illness

Score43210


Who is a contact?

• ? Child• ? Adult• AFB smear pos vs neg

• Xray caregivers


Tuberculin tests

• Mantoux

• Tine test

• False negatives


Sputum/Gastric Aspirates

• Smears and culture are not often positive

• Although a positive sputum or gastric aspirate confirms the diagnosis negative results do not exclude it


Chest X-Ray• TB is most often diagnosed this way. The following changes

are commonly seen in children:– enlarged mediastinal lymph nodes– collapse of a lung segment or lobe (due to pressure on a

bronchus from glands)– pneumonia (lobar or scattered patches) that does not clear on

antibiotics– narrowing of a major bronchus– pleural effusion– calcified lymph nodes– miliary pattern

The more people that look at the X-ray, the closer you get to the correct diagnosis


Some pictures

Remember….– the chest X-ray is often not diagnostic


What’s wide and midline?


Nodal Compression


Easy one: cavitation


Miliary appearance ≡ disseminated TB


Effusion


Could be anything… including TB


Other signs can help…


Well child with a TB Contact

• Is it a real contact?

• Is the child < 5 years?

• What is the tuberculin test?

• Take history and examine child

• CXR

• INH 5mg/kg for 6 mo for well children < 5 yrs with normal CXR’s (or INH/Rif for 3 mo)


Well child with a Positive Tuberculin test

• Is there a TB contact?

• Is the child < 5 years?

• Take history and examine child

• CXR

• INH 5mg/kg for 6 months for well children < 5 years with normal CXR’s (or INH/Rif for 3 months)


Probable TB:

• CXR suggestive of TB and one or more of the following:

1. TB contact2. Positive tuberculin test3. Symptoms of chronic disease eg. Chronic cough or weight

loss4. Persistant CXR changes over 2 – 4 weeks

5. Mx is to treat for TB


Confirmed TB:

• Isolation of the organism on microscopy or culture

• Mx: Treat


When the Diagnosis is in Doubt

• In a young or an ill child, start treatment at once, and reassess once the acute phase has passed

• A follow up X-ray is often very helpful


Document

• Basis for TB diagnosis– Contact

– Tuberculin test

– CXR

– AFB’s

– Carer’s CXR

• Date of COT

• Date of notification


Other conditions to think of:

• The diagnosis of TB in children is often difficult, and it may be confused with the following conditions:– asthma

– whooping cough

– foreign body

– HIV infection

– CF


From now…be a detective

• Take a history• Do an examination – look for hypersensitivity rxns

• Do focused investigations– CXR

– Skin Test

– CXR mother/grandmother

– Find the AFB’s

– If dissemination possible, do a LP


Management of uncomplicated PTB

• Notify

• INH 10mg/kg / RIF 10mg/kg / PZA 20mg/kg for 2 mo

• INH/RIF for 6 mo

• Add ethambutol (15-20mg/kg) for two months if 8 years or older

• Problems………. pto


Problems

• Compliance/doctors/patients

• Combination drugs– INH 30 & RIF 60 & PZA 150

– INH 30 & RIF 60

• HIV


Where

• Clinic

• HIV follow up

Documents

Pulmonary TB : Dr S HarrisPulmonary TB Not an easy diagnosis By Dr S Harris Department of Paediatrics: March 2004 Recent Exam questions • 1999: – Describe how to perform read and