SEVERE MALNUTRITION IN AN ELDERLY PATIENT WITH PULMONARY TUBERCULOSIS: A CASE REPORT

Abstract

Introduction Undernutrition is the single largest population-attributable risk factor for tuberculosis worldwide, and the relationship between the two conditions is bidirectional: nutritional depletion impairs cell-mediated immunity and permits progression to active disease, while active disease drives anorexia, hypermetabolism and accelerated loss of lean tissue. In older adults this interaction is compounded by immunosenescence, inflammaging and the anorexia of ageing, yet the geriatric population remains under-represented in both tuberculosis and clinical nutrition literature. Severe undernutrition at the extreme end of the spectrum, with a body mass index below 14 kg/m², is encountered principally in resource-constrained primary care settings where formal nutritional assessment is seldom performed.1-3 Case Illustration A 73-year-old male farmer presented to a community health centre with one month of productive cough accompanied by rhinorrhoea and exertional breathlessness. Fever and night sweats were absent. He described progressive unintentional weight loss and a one-week decline in appetite, and had smoked ten cigarettes daily for many years. Vital signs were within normal limits, but he appeared cachectic, weighing 40 kg at a height of 170 cm, giving a body mass index of 13.8 kg/m², with a mid-upper arm circumference of 23 cm and a waist circumference of 70 cm. Sputum nucleic acid amplification testing detected Mycobacterium tuberculosis; random blood glucose was 92 mg/dL and human immunodeficiency virus serology was non-reactive. The Mini Nutritional Assessment yielded a total score of 15.5 of 30, placing him in the malnourished category, and simplified geriatric screening confirmed impairment confined to the nutrition domain. He was commenced on a standard six-month antituberculosis regimen together with symptomatic therapy, and a structured, stepwise nutritional prescription with refeeding precautions was formulated.4,5 Discussion This case demonstrates the convergence of four distinct but overlapping constructs in a single patient: protein-energy malnutrition satisfying the Global Leadership Initiative on Malnutrition criteria, disease-related malnutrition with inflammation consistent with cachexia, probable sarcopenia, and the anorexia of ageing. The discussion examines why chronological ageing predisposes to both tuberculosis and nutritional depletion, the discordance observed between body mass index and mid-upper arm circumference in this patient, the derivation of individualised energy and protein targets, the stratification and prevention of refeeding syndrome, the influence of low body weight on antituberculosis drug exposure, and the evidence that nutritional support materially improves tuberculosis outcomes. A discrepancy between the recorded fixed-dose combination tablet number and the patient's weight band is also examined, since it carries direct implications for toxicity in an older adult.6-8 Conclusion Severe undernutrition in an older adult with pulmonary tuberculosis is not a passive comorbidity but a modifiable determinant of survival, treatment success and functional recovery. Nutritional status should be quantified with validated instruments at the point of diagnosis, a numerically explicit and phased nutritional prescription should be issued alongside chemotherapy rather than after it, and drug dosing should be re-verified against actual body weight. Primary care services in high-burden settings are the appropriate place for this integrated assessment to occur.9