Stem : 24 year old young lady came back from Bangladesh recently came to out-patient with complain of a neck lump along with
night sweats, low mood, depression & lack of appetite. Considering this as pathology station answer the following questions.
Q1. What is the diagnosis/differential diagnosis ? TB and lymphoma( NHL)
Q2. What is the histological appearance of TB? Caseous necrosis n granuloma,
langhans type giant cells., AFB
Q3. What are the tests for TB – culture, stain (Ziel-Neelson), sputum examination ,Mantoux
test, PCR to differntiate mycobacteria t.b from other species , Quantiferon (
interferon gamma release assays= IGRA ), FNAC of lymph node.
Q4. For Investigations where wil you send the sputum to? (microbiology lab, cytology lab.)
Q5.What are the other investigations ? (TB PCR, mantoux, IF- gamma, AFB .)
Q6. What is Granuloma? –focal area of chronic inflammation –aggregate of epithlioid
histiocytes (arranged in clusters,little phagocytic activity, produce ACE e.g.
Q7. Types/Classification of Granuloma?
Infection: Tb ,leprosy,syphilis,actinomycosis
Inflammation: sarcoidosis, crohn,PBC, Wegner granulomatosis
Foreign body :beryllium, silica, sutures, talc,
Malignancy : Hodgkin ds
Q8. What is Giant cell of Langerhans? Epitheoid cell, Horseshoe arrangements of
peripheral nucleus at one pole.e.g.TB
Q9.How will do Rapid detection of Mycobacterium ? Recombinase polymerase
Q10. FNAC result shows necrotic tissue, histiocytes, giant cells, what is the diagnosis ? TB
Q11. What are giant cells ? multinucleated cells comprising of macrophages
converted epitheloid cells. Types : histiocytic,langhans,foreignbody,Touton.
Q12. How long does a TB culture take? 18-24 days , 4-6 weeks
Q13. What is the proteinaceous substance that can be found systemically
in TB ? AA amyloid
Q14. What will you do once you collected the sputum sample? (Put in
biohazard bag, inform CDC, microbiology dept, . I wasn’t sure about the UK
equivalent, so I said I will inform the UK equilvalent of CDC and ministry of
health. He laughed really loudly and asked how do we do it in Singapore. I
said online or call)
Q15. What other mycobacterium do you know? Mycobacterium avium
intercellulare, M. ulcerans, M. kansaii
Q16 What is Mycobacterium? Obligatory aerobic ,Non sporulating,nonmotile, weakly
G+ rod( order : actinomycetales)
Q17. How will you label the sputum specimens? Biological Substance Category B –
( highly infectious – red) , diamond mark which is UN3373
Q18. Where wil you put the specimen? in a biohazard bag
Q19. What are the culture media for mycobactetia?
Solid : lowenstein jensen media, middle brooke media and Ogawa
Liquid: BACTEC/MGIT ( mycobacteria growth indicator tube)
Q20. What are the Public health concern/ community concerns?
1. notify the consultant in communicable disease control (CCDC)
2. Avoid work in food factory
3. Use mask during sneezing or coughing
4. takes DOTS ATT,
Q21. What is Contact tracing ? Identification & diagnosis of persons who may have
come into contact with an infected person in last 21 days.
Q22. What is your advice to contacts ? councelling,screening & treatment
of other family members