Biokemistri Nigerian Society for Experimental Biology ISSN: 0795-8080 Vol. 16, Num. 1, 2004, pp. 29-36

Biokemistri, Vol. 16, No.1, June, 2004, pp.29-36

Comparative study of plasma electrolytes (Na, K, Cl, and HCO₃) and urea levels in HIV/AIDS and pulmonary tuberculosis infected subjects

Olaniyan  M. FOLARANMI* and Adesoji A. ADESIYAN  

Code Number: bk04005

Key words:Electrolytes, urea, HIV/AIDS, PTB Mycobacterium Tuberculosis.

Acquired immunodeficiency syndrome (AIDS) is caused by human immunodeficiency virus (HIV) which can be contracted through sexual contact, exposure to blood including sharing contaminated needles and syringes and by certain blood products or other body fluids. Human immunodeficiency virus/acquired immunodeficiency syndrome has been the leading cause of death among young adults in the United state and has a devastating impact on people in the developing countries⁷. The clinical presentation of his disease include pneumonia, fever/pyrexia loss of vision, night sweats, chronic diarrhoea, weight loss, lymphadenopathy, cough, an itch maculopapular generalized skin rash, blue discolouration, anaemia and hairy leukoplakia^{8, 9, 12, 18}.

Mycobacterium tuberculosis is considered as an etiologic agent of tuberculosis and the unifying feature of the genus is an acid fast property^3,6. Tuberculosis is a major cause of morbidity and mortality worldwide and is spread primarily through airborne transportation by aerosolized droplets during coughing, sneezing or talking especially in poorly ventilated areas and over 10 million cases of this disease are diagnosed annually with about 3 million deaths attributed to tuberculosis^4,13,15,21. This disease is characterized by unexplained cough persisting for more than three weeks, haemoptasis pleural pain not associated with an acute illness, loss of appetite spontaneous pneu-mothorax; dehydration/vomiting, unexplained tiredness, loss of weight; high remittent or intermittent pyrexia; pleural effusion, severe and continuous diarrhoea in cases of tuberculosis enteritis, drenching sweats during sleep; and anaemia^10,12.

Factors contributing to the resurgence of tuberculosis in developing countries and problems of its control include co-infection with HIV; emergence of multidrug resistant tuberculosis, inadequate treatment, poverty, malnutrition, over crowing, armed conflict and increasing numbers of displaced persons¹². Diarrhoea, vomiting and excessive sweat, the common features of HIV/AIDS and tuberculosis infection have been described as the common cause of loss of water and electrolytes^{1, 5, 11}.

This recent study was designed to measure the level of urea and electrolytes in patients suffering from HIV/AIDS and pulmonary tuberculosis infection. This may be helpful in the differential diagnosis of these diseases because some of the clinical manifestations are similar.

MATERIALS AND METHODS

Subjects

a)Thirty HIV/AIDS seronegative pulmonary tuberculosis patients with the active infection (15 males; 15 females) aged 20-61 years diagnosed by Ziehl Neelsen staining/demonstration of mycobacterium tuberculosis in sputum and sputum culture on Lowenstein Jensen medium (12). The subjects were also tested for HIV/AIDS infection.

b) 30 HIV/AIDS seropositive mycobacterium tuberculosis free subjects (18 females and 12 males) aged 17-42 years. The subjects’ sputum was also screened for mycobacterium tuberculosis infection as above. HIV/AIDS blood tests were also carried out on each subject and confirmation was done using Western blot.

c) 50 normal subjects free of HIV/AIDS and pulmonary tuberculosis (25 females and 25 males) aged 2-70 years were used for the study. HIV/AIDS and mycobacterium tuberculosis screening and confirmation were carried out on each of the subjects.

Materials

Five to ten milliliters of venous blood was obtained from each of the subjects into lithium heparinized tubes, the plasma was extracted and used for the analysis of urea, electrolytes, HIV/AIDS screening and western blot analysis (carried out on each of the subject groups). The sputum of each of the subjects in each of the subject groups was collected in a sterile universal bottle for ziehl Neelsen staining (3 consecutive times) and cultured on Lowentein Jensen medium for the identification and confirmation of the presence of mycobacterium tuberculosis.

Methods

(a) Electrolytes:-

Potassium (K⁺):-This was analysed by the method described by Terri et al¹⁷ using Teco Diagnostic 4925e Hunter Ave. Anaheim CA. 92807 Reagent set.

Sodium (Na⁺):- It was analysed using the Reagent set (colorimetric method) of Teco Diagnostic 4925e, Hunter Ave, Anahem, CA92807.

Chloride (Cl):- Was analysed by the thiocyanate colorimetric method described by Skeggs et al¹⁶ using Quimica. Clinica Aplicada S.A 43870, Amposta/Spain Reagent set.

Bicarbonate (HCO₃):- was analysed biochemically using the tiration method described by van Slyke¹⁹.

Urea:- It was analysed using Urease- berthelot colorimetric method of Weatherburn²⁰ using the reagent set of Randox Laboratories Ltd. Diamond Road, Crumilin. Co.Antrim, U.K. BT294oy. E-mail @randox.com.

(b) HIV/AIDS Test

   i.HIV screening by the Genie II-HIV1/2-9 a dual recognition Enzyme immunoassay (EIA); a kit of Biorad, 3 boulvard Raymond Poincare 92430 Marnesla Coqutte-France.

 ii.Western blot assay method was used for confirmation at the department of virology university collegeHospitalIbadan.

RESULTS

The results obtained from this present study as shown in tables 1-7 indicate no significant difference in the mean value of 147.0 ± 6.8 (Na⁺),  mmol/L in normal subjects with plasma sodium (Na⁺) Level of 144.8 ± 5.1 mmol/L (Range 134-152), P> 0.05, though this difference is still within the reference range of the normal subjects. The means ± S. D (standard deviation) of 2.53 ± 0.52 (K⁺) mmol/L observed in the tuberculosis subjects was significantly lower than 4.3 ± 0.7 (K⁺) observed in the normal subjects (n=50; Range-3.4-5.3). The chloride concentration of 105.1 ± 4.4 mmol/L observed in the pulmonary tuberculosis patient was significantly higher (P<0.05) than 101.7 ± 3.6 mmol/L in the normal subjects, which also falls within reference range of the normal subjects (97-108 mmol/L). The mean values of bicarbonate (HCO₃) and urea concentration of 23 ± 3.0 mmol/l and28.6 ± 8.5mg/dl respectively observed in PTB patients were significantly lower than those obtained from the normal subjects of 26.4 ± 2.4 mmol/L [HCO₃] and 35.8 ± 8.3 (urea) mg/dl (p<0.05), these values are still within the reference range of the normal subjects (Urea-18-50mg/dl and HCO₃- 22-30 mmol/L). The mean value of 125.8 ± 5.8 mmol/L (Na⁺) obtained from the HIV/AIDS subjects (n=30) was significantly lower than the observed mean of 143.8 ± 5.lmmol/L in the normal subjects [n=50;p<0.05] which also lower than the reference range of the normal subjects [134-152]. 4.9 ± 0.82 [K] mmol/L in the HIV/AIDS infected subjects was significantly higher than 4.3 ± 0.7 (K⁺) mmol/L observed in the normal subjects; though this mean value is still within the reference range of the normal subjects (3.4-5.3mmol/L). The mean value of chloride concentration of 94.1±5.9 mmol/L obtained from the HIV/AIDS subjects was significantly Lower (P<0.05) than the reference range of the normal (97-108mmol/L).

There was no significant difference in the mean values of bicarbonate (27 ± 2.3mmol/L) and urea (37.7 ± 10.5m gld) observed in the HIV/AIDS subjects compared to those of the normal subjects (n=50) of 26.4 ± 2.4mmol/L (HCO₃) and 35.8 ± 8.3 (Urea) mg/d (P<0.05).

The comparative study of the level of the electrolytes and urea of the test subjects indicate higher significant mean values of 4.9 ± 0.82 (K⁺) mmol/L; 27 ± 2.3 (HCO₃) mmol/L and 28.6 ± 8.5mg/dl (Urea) in the pulmonary tuberculosis patients (P<0.05). There was a lower significant mean values (P<0.05) of 125.8 ± 5.8 (Na⁺)

Table 1: Plasma electrolytes and urea levels in pulmonary tuberculosis patients versus the normal subjects

Table 2: Plasma electrolytes and urea levels in HIV/AIDS patients versus the normal subjects

Table 3: Plasma electrolytes and urea levels in HIV/AIDS patients versus the normal subjects

Table 4: Summary mean (x) ± standard deviation of the subject group

Table 5: Range

Table 6: Comparative study of sodium levels in PTB patients that presented with vomiting with the non vomiting PTB and normal subjects

Table 7: Pasma K⁺ values of the icteric (and the anicteric) HIV/AIDS patients versus the pulmonary tuberculosis (PTB) patients and the normal subjects

mmol/L and 94.1 ± 5.9 (CL) mmol/L obtained from the HIV/AIDS patients than 147.0 ± 6.8 (Na⁺) mmol/L and 105.1 ± 4.4 (Cl^-) mmol/L observed in the pulmonary tuberculosis (PTB) patients (P<0.05).

Ten (10) of the thirty (30) HIV/AIDS Patients presented with jaundice. The mean potassium (K⁺) mmol/L value of icteric HIV/AIDS subjects of 5.8  ±0.12mmol/L was significantly higher than the values observed in the anicteric HIV/AIDS patients [4.4 ± 0.55] ; PTB patients (2.53 ± 0.52 mmol/L) and the normal subjects (4.3 ± 0.7 mmol/L0 with P<0.05. The anicteric HIV/AIDS subjects means potassium value (4.4 ± 0.55 mmol/L) shows a non-statistical significant difference (P>0.05) compared to the values observed in the normal subjects (4.3 ± 0.7 mmol/L and a higher significant difference (P<0.05) compared to the mean values in the pulmonary tuberculosis patients (2.53 ± 0.52 mmol/L K⁺). Seventeen (57%) of the 30 PTB patients used were vomiting during this study with X ± S.D of 152.2 ± 3.0 (Na⁺) mmol/L which was significantly higher than those not vomiting with 140.2 ± 3.2 (Na⁺) mmol/L (P<0.005) and than those of the normal subjects P<0.05. The mean value of Na⁺ observed in non vomiting PTB patients (140.2±3.2) was significantly lower than those oft eh normal subjects of 143.8 ± 5.1 (Na⁺) with P<0.05.

DISCUSSION

The lower significant plasma level of sodium (Na⁺) found in HIV/AIDS patients than the normal subjects and the pulmonary tuberculosis (PTB) patients is consistent with the finding of Bevilacqua² which can be attributed to loss of Na⁺ through diarrhoea presented by 21 (70%) of the patients already down with AIDS^{1, 2,10,11}.

The observed significantly higher mean values of sodium (Na⁺) level in the vomiting PTB patients than the non vomiting PTB patients and the normal subjects is attributable to dehydration due to vomiting, muscle wasting, Fever and because sweat is hypotonic compared with plasma^{1, 5, 10, 11, 12}.

It was found that the mean K⁺ level in patients with HIV/AIDS was significantly higher than those of the pulmonary tuberculosis subjects and the normal subjects. The above observation can be attributed to the facts that in HIV/AIDS infection there is the killing of cells by virus, high grade pyrexia/fever [causing the destruction of cells) and therefore leading to the influx of K⁺ from  the cells to the plasma^1,5,14. Another similar reason in support of the above is that 10 (33.3%) of the HIV/AIDS patients presented with jaundice; the mean K⁺ value of which was significantly higher compared to other subject group due to haemolysis^{1, 5,10,11}.

The lower significant mean K⁺ value in pulmonary tuberculosis patients compared to the normal subjects agrees with the facts earlier reported^1,5,10,12 that in stress due to severe/chronic illness thee is increased catabolism of body protein leading to the movement of K⁺ from the intracellular compartment to the plasma and consequently excreted in the urine, sweat and vomiting without any compensatory replacement through food due to anorexia a common feature of PTB patients^10,12.           

The mean value of chloride gave the same pattern as the level of Na⁺ in the subjects because Na⁺ is always (in most cases) in association with Cl therefore the same reason for the level of Na⁺ in the subjects also holds for this. The significantly lower bicarbonate level in the pulmonary tuberculosis patents than the HIV/AIDS and the normal subjects can be attributed to the body’s compensatory mechanism to maintain electrochemical neutrality due to the plasma levels of Na⁺ and especially chloride^1,11.           

The significantly lower level of urea found in pulmonary tuberculosis patients than the HIV/AIDS can be attributed to excessive loss of fluid through diarrhoea manifested by 21 (70%) of the HIV/AIDS patients^1,11,12.

The pattern of electrolytes and urea observed in this study the pulmonary tuberculosis (PTB) and HIV/AIDS patients will therefore be of help in the differential diagnosis and in the understanding of the pathophysiology of the two disease conditions.

REFERENCES

1. Baron D. N., Whicher J. T and Lee K. E. (1989) A new short textbook of chemical pathology. ELBS Fifth edition. Printed and bound in Great Britain by Bulter and Tanner Ltd. Frome and London. Pp 17-32.
2. Bevilacqua M. (1994) Hyponatraemia in AIDS: Bailliere’s clinical Endocrinology and Metabolism. Publisher and place Volume 8, No 4 pages 837-849.
3. Bloom B. R. and Murray C. T. L (1992) Tuberculosis commentary on a recent killer. Science257: 1055-1064.
4. Hamburg M. A., Frieden T. R. (1994) Tuberculosis transmission in the 1990’s. N. Engl J. Med.330:1750-1751.
5. Harold Varley (1988) Practical Clinical Biochemistry, India. Fourth edition Published and Distributors 485, Jain Bhawan, Bhola Nath Nagar Sahsara, Dehli-110032. (India).
6. Hirsch C. S., Johnson J. L. and Ellner J. J. (1999) Pulmanary tuberculosis. Curr. Opin. Pulm. Med.5: 143-150
7. Horowitz H. W., Telzak E. E., Sepkowitz K. A. and Wormser G.P (1998) Human Immunodeficiency Virus infections Part 1 (Review). Disease. A. Monthly Journal44:545-606.
8. Kelly P. (1998) Diarrhoea and AIDS:- Recent development in the African Health (Sept.) pp 16-18.
9. Lloyed A. (1996) HIV infection and AIDS (Review). Papua New Guinea Medical journal.39:174-180.
10. Macleod John (1981) David Son’s Principles and practice of Medicine. Price Thirteenth Edition Publisher by ELBS and Churchill Livingstone. Page 307.
11. Monica Cheesbrough (1998) District Laboratory Practice in Tropical Countries Part 1, Cambridge Low Price Editions, CambridgeUniversity Press. Pages 268-270 and 314-315.
12. Monica Cheebrough (2000) District Laboratory Practice in Tropical Countries Part2, Cambridge   Low Price Editions, CambridgeUniversity Press. Pages 207-212 and 253-266.
13. Murray J.F. (1998) Tuberculosis and HIV infection: A global prospective. Respiration65:335-342.
14. Mwanda O. W. (1997) Haematological changes in Human immunodeficiency Virus infection. East Afr.  Med. J.74: 732-6.
15. Rvigillone Mario C., Snider Jr. D. E. and Kochi. A. Global Epidemiology of tuberculosis. J. Am.  Med. Assoc. (JAMA)273:220-225.                                    
16. Skeggs L. T. Hochstrasser H. C. (1964) Thiocyanate (colorinmetric) method of chloride estimation. Clin. Chem.10: 918-920.
17. Terri A. E. and Sesin P.G (1958) Colorimetric method of Potassium estimation using Sodium Tetraphenylboron. Am. J. Clin path29.86.
18. Todd. J; Balira R., Grosskurth H., Mayand P., Mosha F., Ka-Fina G., Klokke A., Gabone R., Garyole A. and Mayes. R. (1997) HIV-associated adult mortality in a rural Tranzanian population.
19. Van Slyke D. (1922) Titration method of plasma biocarbonate estimation J. Biol. Chem.52:495.
20. Weatherburn M.W (1967) Colorinmetric Urease-Berthelot method of Urea estimation. Anal. Chem.39:971.
21. World Health Organization (1997) Global tuberculosis Programme. Global tuberculosis control. Geneva. The organization report. WHO/TB97: 225.
22. Yoong K.Y. and Cheong I. (1997) Study of Malaysian drug addicts with Human Immunodeficiency J. STD and AIDS8:118-123.