Total lymphocyte count

Nutrition affects immune status both directly and indirectly. Total lymphocyte count and delayed cutaneous hypersensitivity reactions are immune function tests useful in nutrition assessment. 

Total lymphocyte count is obtained from a complete blood count with differential (% lymphocytes x total number of white blood cells). Values less than 1,500 cells/mm3 and 900 cells/mm3 are associated with moderate and severe nutrition depletion, respectively. 

Studies of non-cancer effects in children have indicated neurodevelopmental delays and neurobehavioural effects, including neonatal hypotonia. In children in Seveso who were highly exposed to TCDD, small, transient increases in hepatic enzymes, total lymphocyte counts and subsets, complement activity, and non-permanent chlo-racne were observed. Also, an alteration of the sex ratio (excess female to male) was observed in children born to parents highly exposed to TCDD. 

In simations where CD4 counts cannot be assessed, the presence of a total lymphocyte count below 1200 mm may be used as a substitute indication for treatment. 

Recommended testing should include a white blood cell count and differential to permit assessment of neutropenic side effects. The total lymphocyte count as a measure of ART treatment response is unreliable and not generally recommended. Serum alanine or aspartate aminotransferase (ALT, AST) level determinations are recommended to monitor for hepatotoxicity. Creatinine and phosphate should be measured 4 weeks after initiation of tenofovir. 

Figure 9.3 Mean total lymphocyte count after one course of treatment. Peripheral blood was collected from individuals administered test article (circles) or placebo (squares) on a weekly basis, and subject to flow cytometry analysis to determine mean lymphocyte counts. A standard panel of fluorochrome-conjugated antibodies was used to identify the various lymphocyte sub populations. The solid bar indicates the dosing interval.

A routine WBC count with differential can determine the total lymphocyte count. Total lymphocyte count has been used as ameasure of nutritional status because this changes rapidly with nutrient loss or repletion. This is a relatively gross measure of a patient s immune status, although it has been correlated with patient outcome and risk of infection. 

The frequency of impaired immunocompetence and increased incidence of infection in malnourished patients suggests that certain immune function tests can be used as nutrition status markers. Nutrition affects immune stams either directly, affecting primarily the lymphoid system, or indirectly by affecting cellular metabolism or organ systems that are involved with immune system regulation. Immune fimction tests used in nutrition assessment are the total lymphocyte count (TLC) and DCH reactions. Both tests are simple, readily available, and inexpensive. TLC reflects the number of... 

Lau, B., Gange, S.J., Phair, J.P., Riddler, S.A., Detels, R., and Margolick, J.B. 2003. Rapid declines in total lymphocyte counts and hemoglobin concentration prior to AIDS among HIV-1-infected men. AIDS 17 2035-2044. 

Observational studies Researchers examined the outcomes in 249 paediatric patients with severe combined immunodeficiency [168 -]. Mismatched related donor and unrelated umbilical cord blood transplantation was performed in 175 and 74 patients, respectively. Recipients of umbilical cord blood transplant demonstrated higher frequency of complete donor chimerism (75% vs 33%, p = 0.001), faster total lymphocyte count recovery (at 6months, p=0.001) and discontinuation of immxmoglobulin replacement therapy sooner (at 3 years 45% vs 31%, p=0.023) however, umbilical cord blood transplant also had higher rates of chronic graft-versus-host disease (22% vs 10%, p=s0.03). 

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