Nutrition and HIV infection

Infection by the human immunodeficiency virus (HIV) is characterized by progressive destruction of the immune system, which leads to recurrent opportunistic infections and malignancies, progressive debilitation and death. Malnutrition is one major complication of HIV infection and is recognized as a significant prognostic factor in advanced disease. Malnutrition is multifactorial and poorly treated during the course of HIV. Even if a standardized approach to the management of active weight loss has not been well established, early nutritional intervention is important in HIV infected patients to maximize gain of lean body mass. From early in the era of highly active antiretroviral therapy (HAART), an initial decreased incidence of malnutrition was noted only in western countries while a variety of changes in the distribution of body fat and associated metabolic abnormalities have been recognized under the banner of lipodystrophy.     

Nutrition support of the pediatric patient with AIDS

Maintaining optimal nutrition in the pediatric patient with Acquired Immune Deficiency Syndrome (AIDS) is challenging, but it may be one of the most effective therapies. Patients experience numerous complications that compromise nutritional status. Infection, fever, diarrhea, feeding problems, and decreased intake all contribute to malnutrition, which in turn predisposes the patient even more to infection and malabsorption. Nutrition assessment should be done routinely so that new problems may be identified and treated. High-calorie, high-protein feedings, vitamin supplementation, and, when necessary, gavage feedings or parenteral nutrition are recommended to improve nutritional status and prevent further deficits. Maintaining optimal nutrition in the pediatric patient with Acquired Immune Deficiency Syndrome (AIDS) poses a significant challenge to the health care team. Patients may experience numerous complications that compromise nutritional status. The patient is at high risk for opportunistic infections, especially of the lungs, central nervous system, gastrointestinal (GI) tract, and skin. Such infections are common causes of morbidity and mortality. Impaired nutritional status may further impair the patient's immunocompetence. A study by Kotler and Gaety demonstrated severe progressive malnutrition in adult AIDS patients, with the lowest measures of lean body mass occurring in those patients close to death at the time of the study. While no studies of children with AIDS have been done to date, we have subjectively observed feeding problems, weight loss, and malnutrition in most of the patients we have seen.     

AIDS-related intestinal cryptosporidiosis: role of nutritional support

HIV-related cryptosporidiosis is an opportunistic parasitic infection that may occur in the advanced phases of the disease in case of severe immunodeficiency. It provokes inflammatory diarrhoea with malabsorption and weight loss. Highly active antiretroviral therapy (HAART) and nutritional support are the only treatments in the absence of any efficient therapy. In a young woman affected with vertically transmitted HIV infection, cryptosporidiosis induced severe metabolic imbalance and malnutrition. The contemporary presence of other opportunistic diseases such as oral and pharyngeal candidiasis and disseminated cytomegalovirus disease worsened the symptoms and nutritional alterations. Using specific therapies for these pathogens and adequate nutritional support, both metabolic and nutritional alterations and clinical symptoms were resolved, allowing the commencement of HAART for the improvement of cryptosporidiosis.     

Nutrition care of AIDS patients

Often the complications of the acquired immunodeficiency syndrome (AIDS) have a negative impact on nutritional status. Weight loss and protein depletion are commonly seen among the AIDS population. Though the relationship between disease progression and nutritional status has not been established, maintaining good nutritional status may support response to treatment of opportunistic infections and improve patient strength and comfort. Increased nutrient needs, decreased nutrient intake, and impaired nutrient absorption contribute to malnutrition in AIDS patients. Causes of decreased nutrient intake and absorption may be poor appetite, oral and esophageal pain, mechanical problems with eating, and gastrointestinal complications (diarrhea and malabsorption). Causes of these impediments to maintaining nutritional status are discussed, and suggestions to overcome them are given. Dietitians working with AIDS patients need to understand how the complications of the disease might affect nutritional status so that strategies for nutrition treatment can be developed. Nutrition care of AIDS patients requires that dietitians and their support personnel provide supportive, nonjudgmental care. The patients should be included in decision making regarding their nutrition care. Caring for AIDS patients in the community and through home care agencies represents an area in need of the expertise of a dietetics professional.     

Malnutrition and wasting, immunodepression, and chronic inflammation as independent predictors of survival in HIV-infected patients

To analyze the long-term survival factors associated with HIV infection, a prospective follow-up study of 165 HIV-infected patients was performed after a clinical, nutritional, and biological evaluation. Survival rate could be determined in 129 patients after a follow-up of 42 mo before the use of protease inhibitors. After univariate analysis, multivariate analysis was performed with the Cox regression proportional-hazard model. Survival curves were calculated and compared with the Kaplan, Meier, and log-rank tests. The study also analyzed the factors associated with impaired nutritional status at the beginning of the study and their effects on the long-term follow-up. Factors that could explain body weight loss before the study were the level of intakes, resting energy expenditure, chronic diarrhea, and the number of previous opportunistic infections. In the long-term follow-up, univariate analysis showed that nutritional status could be separated into four classes of body weight loss (BWL) by degree of loss (BWL < or = 5%, 5% < BWL < or = 10%, 10% < BWL < or = 20%, BWL > 20%); lean body mass (adjusted to height), body cell mass, CD4 count, albumin, prealbumin, and C-reactive protein (CRP) were all significant predictors. Age, stage of disease, number of previous opportunistic infections, and antiviral therapies were not associated with a change in survival. With the multivariate model, only CD4 counts, lean body mass/height squared, and CRP remained significant independent predictors of survival after controlling for other factors.     

Advances in nutrition support for quality of life in HIV+/AIDS

Globally, acquired immunodeficiency syndrome (AIDS) is an epidemic, severe and fatal disease. Along with the etiological factors of human immunodeficiency virus infection (HIV+) and decreased immunity, there are a number of other risk factors including opportunistic infection, malnutrition, wasting syndrome, and oxidative stress. The nutritional problems have been shown to be significant and contribute to health and death in HIV+/AIDS patients. Weight loss, lean tissue depletion, lipoatrophy, loss of appetite, diarrhea, and the hypermetabolic state each increase risk of death. The role of nutrition and how oxidative stress is involved in the pathogenesis of HIV+ leading to AIDS is reviewed. Studies consistently show that serum antioxidant vitamins and minerals decrease while oxidative stress increases during AIDS progression. The optimization of nutritional status, intervention with foods and supplements, including nutrients and other bio-active food components, are needed to maintain the immune system. Various food components may be recommended to reduce the incidence and severity of infectious illnesses by forms of bio-protection which include reduced oxidative stress due to reactive oxygen species which stimulate HIV replication and AIDS progression. Probiotics or lactic acid bacteria and prebiotics are sometimes given on the presumed basis that they help maintain integrity of mucosal surfaces, improve antibody responses and increase white blood cell production. People with HIV+/AIDS can be informed about the basic concepts of optimal nutrition by identifying key foods and nutrients, along with lifestyle changes, that contribute to a strengthened immune system. Moreover, nutritional management, counseling and education should be beneficial to the quality and extension of life in AIDS.     

Comparison of methods for assessing nutritional status in HIV-infected adults.

Malnutrition is a frequent complication of human immunodeficiency virus (HIV) infection and is associated with a poor prognosis. To compare different measures of nutritional status in HIV-infected patients, we prospectively studied 88 outpatients seen at a Paris AIDS outpatient clinic for routine follow-up examinations. Nutritional status was assessed according to body weight loss (BWL, 4 classes), anthropometry, bioelectric impedance analysis (BIA), and subjective global assessment of nutritional status (SGA). Malnutrition was diagnosed in 22.4% of subjects using SGA, and 37.1% by BWL. SGA rapidly detected a worsening of nutritional status, while BWL detected malnutrition at an earlier stage. A good correlation was found between SGA class and body composition assessed by anthropometry and BIA. Deteriorating nutritional status diagnosed by SGA correlated with the CDC HIV disease class. SGA, a simple nutritional assessment, can serve as a basis for prescribing artificial nutrition, while BWL detects malnutrition at an earlier stage.     

Assistance nutritionnelle dans la mucoviscidose pourquoi ? quels résultats ?

The prognosis in cystic fibrosis is related to nutritional status. While new enzyme preparations can be used to prepare suitable diets for these patients, the natural history of the disease and the progressive malnutrition may require nutritional support. This is essentially provided as nocturnal enteral feeding and occasionally by the parenteral route. Improvements are obtained not only in terms of anthropometric patterns but also in terms of ventilatory function. Nutritional support may be also extremely useful when preparing patients for transplantation.     

The Role of Nutrition in the COVID-19 Pandemic

SARS-CoV-2, the cause of the COVID-19 disease, is posing unprecedent challenges. In the literature, increasing evidence highlights how malnutrition negatively affects the immune system functionality, impairing protection from infections. The current review aims to summarize the complex relationship between SARS-CoV-2 infection and nutritional status and the effects of malnutrition in terms of disease severity, patients’ recovery time, incidence of complications and mortality rate. Current studies evaluating the possibility of modulating nutrition and supplementation in combination with pharmacological treatments in the clinical setting to prevent, support, and overcome infection are also described. The discussion of the most recent pertinent literature aims to lay the foundations for making reasonable assumptions and evaluations for a nutritional “best practice” against COVID-19 pandemic and for the definition of sound cost-effective strategies to assist healthcare systems in managing patients and individuals in their recovery from COVID-19.     

Malnutrition: Prevalence and its associated factors in People living with HIV/AIDS,in Dilla University Referral Hospital

Background

Literatures on prevalence and factors associated with malnutrition among peoples living with HIV/AIDS are limited in Ethiopia and not well documented either. The proper implementation of nutritional support and its integration with the routine highly active antiretroviral therapy package demands a clear picture of the magnitude and associated factors of malnutrition. The objective of this study is, therefore, to assess the prevalence and factors associated with malnutrition among peoples living with HIV/AIDS.

Methods

Institution based cross sectional study was conducted in Dilla University referral Hospital including adult HIV patients who were in highly active anti retroviral therapy. Interview administered questionnaires were used to collect data on socio demographic factors. Besides, HIV related clinical information was extracted from anti retro viral therapy data base and clinical charts. The nutritional status of the patients was determined by Body Mass Index (BMI) where BMI < 18kg/m² was defined as malnutrition according to World Health Organization (WHO). Binary logistic regression was used to assess association between different risk factors and malnutrition. Confidence interval of 95% was considered to see the precision of the study and the level of significance was taken at α <0.05.

Results

A total of 520 patients were included in the analysis. The overall prevalence of malnutrition was 12.3% (95% CI 9.5–15.0). After full control of all variables; unemployment (OR = 3.61, 95% CI: 3.6 − 7.76), WHO clinical stage four (OR = 12.9, 95% CI: 2.49− 15.25), gastrointestinal symptoms (OR = 5.3, 95% CI: 2.56 − 10.78) and previous (one) opportunistic infection (OR = 3.1, 95% CI 2.06 − 5.46), and two & above previous opportunistic infections (OR = 4.5, 95% CI: 3.38 − 10.57) were significantly associated with malnutrition. However, moderately poor economic condition was found to be protective factor for malnutrition (OR = 0.4, 95% CI: 0.14 − 0.95).

Conclusion

Unemployment, WHO clinical AIDS stage four, one & more number of previous opportunistic infections and gastrointestinal symptoms were found to be important risk factors for malnutrition among People Living with HIV/AIDS. From this study it has been learnt that nutritional programs should be an integral part of HIV/AIDS continuum of care. Furthermore, it needs to improve household income of PLHIV with employment opportunity and to engage them in income generating activities as well.     

Nutritional management of the patient with chronic obstructive pulmonary disease.

The prevalence and prognostic importance of malnutrition in chronic obstructive pulmonary disease (COPD), the factors that contribute to development of nutritional depletion, and the available evidence regarding effects of nutrition support in these patients are the subjects of this review. Nutritional depletion, as indicated by weight loss and loss of lean body mass, is a common complication of advanced COPD (particularly, but not limited to, the emphysematous type). Low body weight or recent weight loss and in particular depleted lean body mass in patients with COPD have been shown to be independent predictors of mortality, outcomes after acute exacerbations, hospital admission rates, and need for mechanical ventilation. The factors thought to contribute to nutritional depletion in these patients include elevated resting and activity-related energy expenditure, reduced dietary intake relative to resting energy expenditure, accelerated negative nitrogen balance, particularly during acute exacerbations of COPD, medication effects, and perhaps most importantly an elevated systemic inflammatory response. Studies to date suggest that, although it can help limit weight loss and negative energy balance in these patients, the effect of nutritional supplementation alone on clinically significant outcomes such as pulmonary function and exercise capacity is minimal. However, nutritional supplementation may have a role in the management of COPD when provided as part of an integrated rehabilitation program incorporating a structured exercise component as an anabolic stimulus.     

Tuberculosis, human immunodeficiency virus infection, and malnutrition in Burundi.

In order to compare the nutritional status of tuberculosis (TB) patients who were human immunodeficiency virus (HIV)-seropositive with those who were seronegative, we carried out a cross-sectional anthropometric and biochemical assessment, together with bioelectrical impedance analysis (BIA) of the nutritional status of TB patients hospitalized in the Department of Internal Medicine, Bujumbura University Hospital, Burundi, East Africa. Of the 65 TB patients (33 pulmonary, 6 extrapulmonary, and 26 disseminated TB), 50 (76.9%) were HIV-seropositive (HIV+). When assessed according to anthropometric, BIA, and biochemical variables, HIV+ TB patients had more pronounced malnutrition than HIV- patients. Similar results were obtained when the comparison was restricted to patients with only pulmonary TB: HIV+ patients were more malnourished than HIV- patients. The results according to anthropometric measurements were: weight loss (13.5% of HIV- patients versus 26.4% of HIV+ patients, P = 0.005), body mass index (18.6 versus 15.1, P = 0.003), fat free mass (FFM) (13.9 versus 11.9, P < 0.01), and body fat (BF) (4.55 versus 3.71, P = 0.03) expressed per unit height2. BIA showed that the difference in FFM between HIV- and HIV+ TB pulmonary patients was mostly due to a decrease in body cellular mass. Measurements of albumin, prealbumin, and transferrin showed a marked decrease in all three markers in HIV+ TB pulmonary patients. The nutritional status of HIV+ patients with disseminated versus pulmonary TB was similar. The nutritional status of HIV+ TB patients is far worse than that of HIV- TB patients. In such patients, anthropometry underestimates the degree of malnutrition because it does not account for the water component of FFM. Nutritional status should be assessed and nutritional intervention should be provided in an attempt to improve the prognosis of TB patients, especially those who are infected by HIV.     

腹膜透析患者营养指标的评估

目的 :　对腹膜透析患者的一些营养指标进行评估。方法 :　对 90例持续性不卧床腹膜透析 ( CAPD腹透 )患者进行主观综合性营养评估 ( SGA)、膳食调查、直接人体测量、生化参数的测定 ,计算氮出现率相当蛋白 ( n PNA)、瘦体重和 %瘦体重。结果 :　依据 SGA评分 ,在营养良好、轻中度营养不良及重度营养不良三组间进行以下指标比较 :平均每日每公斤体重能量和蛋白质摄入 ( DEI、DPI)、血白蛋白、n PNA、瘦体重及 %瘦体重 ,均有显著性差异 ( P<0 .0 0 1～ 0 .0 5 )。但营养良好组的 DPI和 DEI异常率 70 .2 1 % ,血白蛋白和 %瘦体重异常率 31 .91 %和 5 1 .0 6% ,而轻中度营养不良组血白蛋白和 %瘦体重正常率为 49.39%和 67.74% ,仅重度营养不良组中各指标异常率均在 80 %以上。直接人体测量指标体重指数、三头肌皮褶厚度和上臂肌围在本组患者中的异常率为 4.44% ,6.67%及 1 3.33%。血前白蛋白、转铁蛋白与白蛋白有显著相关 ( P<0 .0 0 1 ) ,与 DPI、DEI、n PNA及 %瘦体重均无相关。结论 :　SGA是评价腹透患者营养状况的简便方法 ,但还需其它反映营养状况不同侧面的指标的补充 ,如 DEI、DPI、血白蛋白、n PNA、瘦体重及 %瘦体重。其中用肌酐动力学公式计算瘦体重是反映肌肉蛋白质贮存的有效方法。直接人体测?     

Nutritional status of adult inpatients in Bujumbura, Burundi (impact of HIV infection).

OBJECTIVE: To determine the prevalence and analyse the characteristics and causes of malnutrition among inpatients in an HIV highly endemic area. DESIGN: Prospective cross-sectional study. SETTING: Department of Internal Medicine, University Hospital, Bujumbura, Burundi. SUBJECTS: 226 adult inpatients. MAIN OUTCOMES MEASURES: Evaluation of nutritional status using anthropometry. Degree of malnutrition defined by the percentage of body weight loss (BWL), calculated by reference to the usual body weight. RESULTS: Among the 226 patients recruited (mean age: 34.4 +/- 11.9 y, M:F sex ratio: 1.72), 102 (45.1%) were HIV seropositive. 62 (60.8%) of these HIV seropositive were AIDS cases. The AIDS defining criterion was 'wasting syndrome' for 25 (40.3%) and opportunistic infection (OI) for 37 (59.7%) including 34 cases of tuberculosis (TB). The nutritional status of 119/226 patients (52.7%) was normal (BWL < or = 10%). Moderate malnutrition (10% < or = BWL < or = 20%) was observed in 47 (20.8%) and severe malnutrition (BWL > 20%) was observed in 60 (26.5%). HIV seroprevalence and, among HIV seropositive subjects, the percentage of AIDS cases increased according to decreasing level of nutrition (Chi2 for trends: P < 0.001 in both instances). The fat free mass mass of malnourished subjects was lower and the fat body mass was higher among HIV seropositive subjects than HIV seronegative subjects. Among HIV seropositive subjects, malnutrition was associated with TB (P < 0.001) and dysphagia (P < 0.05). Among HIV seronegative subjects, malnutrition was associated with decreased food availability (P < 0.003) and TB (P < 0.05). One week after admission, the mortality rate was higher among HIV seropositive subjects (10.8%) than seronegative subjects (2.4%, P=0.009). Other factors associated with death were decreased fat free mass (P < 0.01) and tricipital skinfold thickness (P < 0.04). CONCLUSIONS: The prevalence of malnutrition is high among the inpatients investigated. Main factors are HIV infection and TB. Strategies adapted to the African context should be developed to prevent, detect and treat malnutrition and associated factors, particularly among HIV seropositive subjects.     

AIDS Presenting in an Adolescent Male With Persistent Conjunctivitis and Eye Pain

An adolescent male with persistent conjunctivitis and an episcleral nodule presented with new-onset focal seizures and headaches. The patient was found to have cotton wool spots and papilledema on retinal examination. He was ultimately diagnosed with HIV retinopathy and AIDS. Ocular manifestations are rare presenting symptoms of AIDS among adolescents in the United States. Ocular disease in pediatric HIV/AIDS patients is most often caused by opportunistic infections. HIV retinopathy, the most common cause of blindness in patients with HIV, is usually a late disease manifestation. It is important for providers caring for adolescents to be aware of the potential ocular manifestations of HIV/AIDS. Teenagers are less likely to be aware of their HIV status and less likely to be tested for HIV, despite high risk exposures, and therefore, universal and routine HIV screening is recommended for all patients.     

Nutrition and alcoholic liver disease

While the rate of malnutrition is relatively modest in alcoholic patients without alcoholic liver disease, the rate of malnutrition is virtually 100% in patients with alcoholic hepatitis and/or alcoholic cirrhosis. The reasons for malnutrition in the alcoholic hepatitis patient include various factors such as anorexia, poor diet, malabsorption, and altered metabolic state. When the patient is hospitalized, the malnutrition frequently worsens because of fasting for tests, continued anorexia, and complications such as gastrointestinal bleeding. Patients with severe acute hepatitis appear to be both hypermetabolic and hypercatabolic, whereas data are much more conflicting concerning patients with more stable liver disease. Most studies suggest that patients with alcoholic liver disease require at least 60 g of protein per day to maintain positive nitrogen balance. Consistent alterations in plasma amino acid profiles occur in alcoholic liver disease, and specialized nutritional formulations have been devised to correct this amino acid profile with the intent of improving overall nutritional status, hepatic encephalopathy, and mortality. The effects of nutritional support (including use of specialized products) on outcome, on acute hepatic encephalopathy, and on chronic or latent portal systemic encephalopathy are reviewed.     

Measuring nutritional status in children with chronic kidney disease

Children with chronic kidney disease (CKD) are at risk of protein-energy malnutrition. Existing clinical practice guidelines recognize this and recommend specific methods to assess nutritional status in patients with CKD. This review summarizes the methods for nutritional assessment currently recommended in the United States for children with CKD and details the strengths and limitations of these techniques in the clinical setting. Dietary assessment, serum albumin, height, estimated dry weight, weight/height index, upper arm anthropometry, head circumference, and the protein equivalent of nitrogen appearance are reviewed. We also describe methods for body-composition assessment, such as dual-energy X-ray absorptiometry, bioelectrical impedance analysis (BIA), total body potassium, densitometry, and in vivo neutron activation analysis, pointing out some advantages and disadvantages of each. In CKD, fluid overload is the most important factor leading to misinterpretation of nutritional assessment measures. Abnormalities in the distribution of fat and lean tissue may also compromise the interpretation of some anthropometric measures. In addition, metabolic abnormalities may influence the results obtained by some techniques. Issues specific to evaluating nutritional status in the pediatric population are also discussed, including normalization of nutritional measures to body size and sexual maturity. We stress the importance of expressing body-composition measures relative to height in a population in whom short stature is highly prevalent.     

Zinc deficiency in head and neck cancer patients.

Although a great deal of attention has been given to protein and calorie malnutrition in patients with head and neck cancer, zinc status has not been assessed properly in such patients in the past.

In this study we characterized zinc status by cellular zinc criteria and assessed several measures of protein and calorie malnutrition in patients with head and neck cancer. We determined prognostic nutritional index (PNI) based on serum albumin, serum transferrin, triceps skin fold measures, and delayed hypersensitivity, as proposed by Buzby et al. In this study, the baseline zinc status and PNI of 60 head and neck cancer patients were correlated with the tumor size and overall stage of the disease.

Our results showed that the tumor size and overall stage correlated significantly to zinc status whereas no correlation was seen with PNI, alcohol intake, or smoking in our study subjects.

We conclude that zinc status is a better indicator of tumor burden and stage of the disease in head and neck cancer patients than the patients' overall nutritional status.     

Estimating the effect of recurrent infectious diseases on nutritional status: sampling frequency, sample-size, and bias

There is an ongoing interest in studying the effect of common recurrent infections and conditions, such as diarrhoea, respiratory infections, and fever, on the nutritional status of children at risk of malnutrition. Epidemiological studies exploring this association need to measure infections with sufficient accuracy to minimize bias in the effect estimates. A versatile model of common recurrent infections was used for exploring how many repeated measurements of disease are required to maximize the power and logistical efficiency of studies investigating the effect of infectious diseases on malnutrition without compromising the validity of the estimates. Depending on the prevalence and distribution of disease within a population, 15-30 repeat measurements per child over one year should be sufficient to provide unbiased estimates of the association between infections and nutritional status. Less-frequent measurements lead to a bias in the effect size towards zero, especially if disease is rare. In contrast, recall error can lead to exaggerated effect sizes. Recall periods of three days or shorter may be preferable compared to longer recall periods. The results showed that accurate estimation of the association between recurrent infections and nutritional status required closer follow-up of study participants than studies using recurrent infections as an outcome measure. The findings of the study provide guidance for choosing an appropriate sampling strategy to explore this association.     

Energy expenditure in HIV infection

Energy intake recommendations for adults should be based preferably on direct measurements of total daily energy expenditure (TDEE) in corresponding populations who are maintaining healthy body weight and satisfactory physical activity levels. During adolescence, pregnancy, and lactation, energy requirements should be based on TDEE plus the additional energy required to advance these physiologic states. With illness, energy expenditure and energy intake change, but nutritional intervention is not necessarily beneficial. This article reviews data on energy expenditure in HIV infection with a focus on adults, adolescents aged ≥14 y, and pregnant and lactating women. Resting energy expenditure (REE) in adults with untreated asymptomatic HIV is ~ 10% higher than in healthy control subjects. In asymptomatic adults receiving antiretroviral therapy, REE may be similarly increased. HIV wasting and secondary infections are also associated with increased REE. In contrast, TDEE is typically normal in asymptomatic HIV and decreased in HIV wasting and secondary infection. No direct measurements of REE or TDEE are available in adolescents or in pregnant or lactating women with HIV. On the basis of current data, energy intake may need to increase by ~ 10% in adults with asymptomatic HIV to maintain body weight. In adolescents and in pregnant and lactating women with asymptomatic HIV, energy requirements should approximate recommendations for their uninfected counterparts until further data are available. In the resource-rich world, the energy expenditure changes associated with HIV are unlikely to contribute to significant weight loss. More data are needed on energy expenditure in HIV-infected populations from developing nations, where concurrent malnutrition and coinfections are common.