Response to "Miliary tuberculosis disease complicated by Pott's abscess in an infant: Seven-year follow-up".

Sir,

Miliary tuberculosis (TB) is an infection of disseminated hematogenous disease caused by the bacterium Mycobacterium tuberculosis (Mtb). The clinical picture produced by lymphohematogenous dissemination depends on the quantity of organisms released from the primary focus and the adequacy of the host's immune response.[1] We agree with the comments stating that immunocompromised individuals are generally more prone to miliary TB.[2] As the authors mentioned, miliary diseases are found to be significantly more common in human immunodeficiency virus (HIV)-infected children (24.0%) compared to non-HIV-infected children and untested children (2.9%). In non-HIV-infected children, miliary disease was predominantly documented in children below 3 years of age as in our case.[3] Although it was reported that HIV infection incidence has increased in the last decade in Turkey, the total number of pediatric HIV infection cases (in the age group of 0-9 years) between 2007 and 2011 was 27.[4] Our patient's anti-HIV antibody test was negative.[5] Other immunological studies were not found abnormality to be associated with primary immunodeficiency. He recovered with anti-TB treatment and during the 7-year follow-up, any clinical situation that refers to immune deficiency did not occur. In children, Bacillus Calmette-Guérin (BCG) has been demonstrated to prevent disseminated TB, miliary TB, and TB meningitis.[6] Our patient had not received the BCG vaccine.

Interferon-gamma release assays (IGRAs) have several advantages over tuberculin skin test (TCT). IGRAs have greater specificity than TST and can greatly reduce the number of false positive results in children who have received a BCG vaccine or who have been exposed to nontuberculous mycobacteria.[7] However, in children below 5 years of age there is uncertainty about the use of IGRAs. For this age group, there is not enough data and it was reported that indeterminate/invalid results seemed to be higher in infants and toddlers than in older children.[5] Although there is no clear data currently about the use of IGRAs in children below 5 years of age, they are commonly used tests at present. But 7 years ago, it was not easily available in Turkey. Also, 7 years ago there were not sufficient data about the usage of IGRAs. Therefore, we did not use this test at that time.

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Conflicts of interest

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