DIAGNOSIS VALUE OF BONE MARROW STUDY IN THE DISSEMINATED INFECTION BY MYCOBACTERIA: CASE REPORT

The bone marrow examination is useful in order to g et an etiologic diagnosis of cytopenias and for the detection of opportunistic diseases in immunocompro ised patients. Nevertheless, its role in the diagn osis of invasive infections caused by mycobacterium has not been clearly defined. We describe the case of a 42year-old woman who was admitted to study anemia, di rrhea and constitutional syndrome during two months with medical history of human immunodeficien y virus-1 infection, old intravenous drug user, hepatitis C virus carrier, as well as having lymph node tuberculosis and tuberculous meningitis during six years. The hematologic assessment was requested for the peripheral blood examination, which showed severe hyporegenerative anemia, rouleaux, anisopoik ilocytosis and neutrophilia. In the bone marrow bio psy imprint we observed a very hypoplastic eritroid ser ies and many macrophages with spread granularity an d cytoplasm, similar to the Gaucher’s cells, which pr esented erythrophagocytosis and birefringence enlar ge forms scattered throughout the smear, suggesting my cobacteria, with these findings, we established the diagnostic suspicion of disseminated mycobacterial disease and started the empirical treatment for Mycobacterium avium intracellulare-tuberculosis on the same day of the procedure, the etiology infe ction was later confirm by cultures. In this case, the bone m arrow examination allowed to establish an early dia gnostic suspicion from the hematology laboratory and to sta rt the treatment before the microbiologic result.


Disseminated
Mycobacterium tuberculosis infection with involvement of liver, spleen and bone marrow is a rare complication of Human Immunodeficiency Virus (HIV) and tuberculosis coinfection and its nonspecific presentation is a challenge for diagnosis (Asl et al., 2011). The Mycobacterium avium complex involves the most common atypical mycobacteria to cause disease in HIV/acquire inmuno deficiency syndrome patients with a low T-lymphocyte CD4+ count (Cortez-Escalante et al., 2012).
The Bone Marrow (BM) examination is useful in order to get an etiologic diagnosis of cytopenias and for the detection of opportunistic diseases in immunocompromised patients (Woessner and Brichs, 2006).
The role of BM study in the diagnosis of invasive infections caused by mycobacterium has not been clearly defined. Nevertheless, across the years, some studies have demonstrated that not only the diagnostic sensitivity of BM cultures was equal to that of blood cultures (Akpek et al., 2001), but also the histopathological examination of BM resulted in relatively rapid identification of this kind of infections, frequently the histology and culture studies results are available after initiation of the treatment (Rose et al., 2011). We report a case in which the bone marrow study (touch imprint and biopsy) was determinant for beginning the empirical treatment for mycobacteria.

Medical History
A 42-year-old woman was admitted to study anemia, diarrhea and constitutional syndrome during 2 months. She was an old intravenous drug user with Human Immunodeficiency Virus-1 (HIV) infection during 14 years (C3 stage) with irregular adherence to the antiretroviral therapy, as well as having lymph node tuberculosis and tuberculous meningitis during 6 years and being a hepatitis C virus carrier during a year. In the initial evaluation at the emergency room was noteworthy: Fever, hypotension, severe general affectation, mucocutaneous paleness, oropharynx candidiasis, hepatosplenomegaly and high LDH and PCR levels.
The hematologic assessment was requested for the peripheral blood examination because of anemia. We found severe hyporegenerative anemia, rouleaux, anisopoikilocytosis and neutrophilia with high granular density, therefore we proceeded to the bone marrow study. In the biopsy imprint we observed a very hypoplastic eritroid series, normal granulocytes, 1% blasts, 5% normal lymphocytes and many macrophages with spread granularity and cytoplasm, similar to the Gaucher's cells, which presented erythrophagocytosis and birefringence elongated forms scattered throughout the smear, suggesting infection by mycobacteria ( Fig. 1A and B). With these findings, we established the diagnostic suspicion of disseminated mycobacteria disease and started the empirical treatment for Mycobacterium Avium Intracellulare (MAI)-tuberculosis on the same day of the procedure.

Histopathological and Microbiological Findings
The Ziehl-Neelsen stain in bone marrow biopsy showed a lot of acid-alcohol-resistant bacilli (Fig. 1C). Some days later, MAI was isolated from the blood, bone marrow and colony biopsy cultures. Despite the treatment, the patient persisted with fever and altered level of consciousness, dying at the 18th day of hospital stay.

CONCLUSION
In the disseminated infection by MAI, only the BM cultures do not give an additional diagnostic value respect to the blood cultures. Successful detection of organisms in bone marrow specimens requires the use of special stains and sensitive cultures techniques. It seems that only a minority of patients are expected to have caseating granulomas on histopatological examination of bone marrow (Hakawi and Alrajhi, 2006). However, it has been studied before that the myelogram and the blood cultures together seem to have a higher value for the diagnosis of opportunistic infections (Ker et al., 2002). An advantage of the bone marrow biopsy is the rapid turnaround time, with most results available within 24 hours and it is a safe and simple procedure. Patients with an uncertain diagnosis should be referred for bone marrow aspiration as soon as possible, preferably before initiation of tuberculosis treatment, although this should not delay treatment initiation if indicated (Rose et al., 2011).
In this case report, the BM examination allowed to establish an early diagnostic suspicion from the hematology laboratory and to start the treatment before the microbiologic result.