Haematological Profiles of Patients with Extra-pulmonary Tuberculosis

Tuberculosis (TB) is a disease caused by bacteria called Mycobacterium tuberculosis. We aimed to evaluate the complete blood count (CBC) and erythrocyte sedimentation rate (ESR) of confirmed extra-pulmonary tuberculosis (EPTB) patients attending clinic at the University of Nigeria Teaching Hospital (UNTH), Ituku-Ozalla, Enugu. A total of 90 confirmed extra-pulmonary tuberculosis patients consisting of male (n = 38) and female (n = 52), aged 15 to 60 years attending clinic participated in this study. CBC and ESR were analysed using Haematological Auto Analyzer and Westergren method respectively. Haemoglobin and haematocrit values across the three age groups (15-30, 31-45, 46-60 years) were significantly lower (p < 0.05) than the control value in both male and female extra-pulmonary tuberculosis patients. Erythrocyte sedimentation rate, white blood count, platelet and neutrophil values across the three were significantly higher (p < 0.05) than the control values in both male and female extra-pulmonary tuberculosis patients. Extra-pulmonary tuberculosis was observed more in females than the males and was relatively higher in older patients (above 46 years) than younger patients (below 46 years). This study was able to show that different haematological parameters such as haemoglobin, haematocrit, Erythrocyte sedimentation rate, white blood count, platelet and neutrophil could serve as hallmark and help in early diagnosis of extra-pulmonary tuberculosis.


Introduction
Tuberculosis is an airborne infectious disease that most commonly affects the lungs where it is called pulmonary tuberculosis. When the infection occurs in any other parts of the body, it is called extra-pulmonary tuberculosis [1]. Tuberculosis is a major public health problem in Nigeria, a country of 169 million inhabitants, with the country currently ranking 10 th among the 22 high TB burden countries of the world and fourth highest in Africa (after South Africa, Ethiopia and DR Congo) [2]. Overall case notifications have consistently increased in the country, but these seem to have plateaued since 2008 despite the more intensified control activities. Out of 97,853 notified TB cases in 2012, 52,901 (59%) were confirmed through smear-microscopy, 32,972 (37%) were based on a clinical diagnosis (smear-negative), and only 4,432 (5%) were extra-pulmonary TB. The overwhelming number of TB case notifications in 2012 (93%) were among patients who had not been treated previously [2]. TB case notification for all forms of TB in 2012 in South East Zone of Nigeria was 41 per 100,000 populations [3]. TB burden in Nigeria is further compounded by the high prevalence of HIV/AIDS of 4.1% among the general population. In 2012, 86% of registered TB patients were tested for HIV; of these, 23% were found to be HIV-positive [4]. TB still constitutes a serious public health problem in Nigeria, despite the implementation of the DOTS strategy since 1993 and subsequent adoption of the WHO Stop TB strategy in 2006.
Results from the national TB prevalence survey in Nigeria have provided a robust direct measurement of TB disease burden in the country for the first time. Before survey results became available, indirect estimates of TB disease burden were calculated based mainly on reported TB case notification data and expert opinion about the levels of under reporting and under diagnosis of cases. Case notification data were known to under estimate the true burden due to recognized problems with case detection [5]. The prevalence of TB disease varied geographically, and was considerably higher in urban compared with rural areas [6].
Accordingly, it was deemed necessary to conduct a study in order to obtain the haematological profiles of patients with extra-pulmonary Tuberculosis attending clinic at the University of Nigeria Teaching Hospital (UNTH), Ituku-Ozalla, Enugu, South-East, Nigeria.

Materials and Methods
This study adopted the survey design and was conducted at the University of Nigeria Teaching Hospital, Ituku-Ozalla, Enugu, Enugu State, Nigeria. Ninety confirmed extrapulmonary tuberculosis patients consisting of male (n = 38) and female (n = 52), aged 15 to 60 years attending clinic at the UNTH and 30 apparently healthy age and gendermatched control subjects (made up of 15 males and 15 females), consisting of 5 subjects from each of three age groups (15-30, 31-45 and 46-60 years) participated in this study. The extra-pulmonary tuberculosis patients were identified and confirmed clinically by the clinicians. Standardized predesigned questionnaire was used to collect data about age, gender, life style, socio-economical status and education from all participants.

Sample Collection and Preparation
Sputum samples were collected from extra-pulmonary tuberculosis patients in a sterile container and smears were prepared stained with Ziehl Neelsen stain by using standard protocol [7]. Blood samples were collected from patient into EDTA containers and analyzed using haematological auto analyzer (Abacus Junior 5 Haematological Auto Analyzer) [8] for different haematological parameters. Erythrocyte sedimentation rate (ESR) was determined using Westergreen method [9].

Ethics
Ethical approval for the study was obtained from the Health Research and Ethical Committee of the University of Nigeria Teaching Hospital, Ituku-Ozalla, Enugu. Also, oral informed consents were obtained from the patients who participated in the study.

Statistical Analysis
Statistical analysis was done with statistical package for social science (SPSS) computer software version 21. Data were subjected to descriptive statistics and analyzed using student t-test and one-way analysis of variance. Probability value p<0.05 was considered statistically significant.

Results
A total of 90 confirmed extra-pulmonary tuberculosis patients and 30 healthy controls participated in this study. The age of the patients and controls were between 15-60 years. For the extra-pulmonary tuberculosis patients, 38 (42.2%) were male and 52 (57.8%) were female while for the control subjects, 15 (50%) were male and 15 (50%) were female ( Figure 1). Haemoglobin and haematocrit values across the three age groups (15-30, 31-45, 46-60 years) were significantly lower (p < 0.05) than the control value in both male and female extra-pulmonary tuberculosis patients. Erythrocyte sedimentation rate, white blood count, platelet and neutrophil values across the three age groups were significantly higher (p < 0.05) than the control values in both male and female extra-pulmonary tuberculosis patients.

Discussion
Tuberculosis is a contagious bacterial infection that mainly involves the lungs, but may spread to other organs [10].  [13]. This could be attributed to the fact that women have less access to tuberculosis treatment and prevention services than men and are unlikely to undergo sputum smear examination. Women in some contexts have difficultly accessing TB services because male family members are unwilling to pay for these services, women's health may not be considered as important as that of male family members, or because TB in women is more stigmatized than in men. Women have a higher prevalence of extra-pulmonary tuberculosis than men, particularly genital TB [14], which is difficult to diagnose and has been identified as an important cause of infertility in settings with high TB incidence [15]. On the contrary, in a retrospective review by Chen et al., 2011 [16]  In this study, extra-pulmonary tuberculosis occurred mostly in mature and productive age group of 46-60 years.
This observation is in line with the studies carried out by Amin et al., 2011 [18] and Ullah et al., 2009 [19] which showed that majority of the patients (82%) were above/older than 40 years of age. One of the most recognized consequences of aging is a decline in immune function. The effects of aging on the immune system are widespread and affect the rate at which naive B and T cells are produced as well as the composition and quality of the mature lymphocyte pool. This could account for the high prevalence of extra-pulmonary tuberculosis within the age range of 46-60 years. Also, the risk of acquiring TB infection increases with age because of increasing number and higher frequency of contacts.
There was a high significant (p<0.05) decrease in the values of haemoglobin and haematocrit of both males and females subjects in comparison with the control (tables 1 and 2). This could be attributed to invasion of bacteria which leads to activation of T-lymphocytes and macrophages, which induce the production of the cytokines causing diversion of iron into iron stores in the reticulo-endothelial system resulting in decreased iron concentration in the plasma thus limiting its availability to red cells for hemoglobin synthesis [20,21]. This finding is in agreement with Muhammad and Hayder 2011 [22] and Eyshi et al., 2009 [23].  In this study, it was found that the values of erythrocyte sedimentation rate (ESR) for both males and females patients with extra pulmonary tuberculosis were highly significantly increased (p < 0.05) more than the control. This is in line with the study carried out by Anju, 2011 [24] in which ESR was raised in 82-95% of patients. On the contrary, ESR which is usually expected to be raised in a patient with extra pulmonary tuberculosis, was < 30mm/hr in first hour in about 14% and >30 mm/hr in first hour in about 86% cases [25].
The platelet count of both extra-pulmonary tuberculosis male and female patients was highly significantly increased (p < 0.05) more than the control. This may be attributed to the reactive thrombocytosis which is found in a number of clinical situations including infectious diseases such as tuberculosis [26].

Conclusion
Extra-pulmonary tuberculosis was present more in females and was relatively higher in older patients. Different haematological parameters like Erythrocyte sedimentation rate (ESR), platelets, leukocytes and toxic granulated neutrophilia work as hallmark and help the clinicians in early diagnosis of the disease. The common risk factors contributing to the dissemination of the tuberculosis in the target area population include malnutrition, smoking tobacco, living in shared houses, illiteracy and poverty.