Changes of zinc values in children during malignant disease

Post-Therapy Profile of Serum Total Cholesterol, Retinol and Zinc in Pediatric Acute Lymphoblastic Leukemia and Non-Hodgkin's Lymphoma

OBJECTIVE

To assess serum albumin, total cholesterol, retinol, zinc and hemoglobin in children who had completed treatment for acute lymphoblastic leukemia (ALL) and Non-Hodgkin's lymphoma (NHL).

METHODS

The above parameters were analyzed in 105 ALL and NHL and 108 age and sex-matched controls. Serum albumin, serum cholesterol and hemoglobin were estimated by colorimetric methods. Serum retinol was estimated by HPLC and serum zinc was estimated by atomic emission spectrophotometer (ICP-AES). Comparisons were made to stage of treatment (maintenance 6 with post-therapy), type of treatment (chemotherapy and radiation with only chemotherapy) and type of malignancy (ALL with NHL).

RESULTS

Only serum albumin in patients included at Maintenance(6) was significantly higher (t = 2.31, p = 0.05) than post-therapy patients. No significant difference in serum values was observed by type of treatment. Only total cholesterol was significantly higher in NHL patients than in ALL patients (t = 1.954, p = 0.05). Patients had comparable serum levels to that of controls. However, in patients and controls more than 75% children had deficient serum retinol levels, (< than 0.6989 micromol/l, or 20 microg/dl). Further, 75% patients and 54.7% controls had serum retinol levels less than 0.3439 micromol/l or 10 microg/dl.

CONCLUSION

The results of the present study indicate that cancer and its treatment did not have any long-lasting effect on serum albumin, total cholesterol, retinol, zinc and hemoglobin. Majority of subjects had low serum retinol suggestive of depleted liver reserves. The deficient serum retinol levels (< than 0.6989 micromol/l, or 20 microg/dl) in at least 75% of the patients and controls probably reflect poor dietary intake. A higher percentage of patients with low serum retinol levels may also be attributed to the possibility of urinary losses of retinol that occur during episodes of infection while on immunosuppressive anti-cancer drug therapy.

Clinical and laboratory assessment of zinc deficiency in Dutch children. A review

The clinical spectrum of acrodermatitis enteropathica (n = 226) is compared with symptoms reported in other Zn deficiencies: total parenteral nutrition without Zn (n = 21), protein energy malnutrition (n = 24), gastrointestinal disease (n = 79), geophagia (n = 227), and dietary low intake (n = 23). Common features of deficiency are diarrhea, recurrent infection, and growth retardation. Dermatitis is less common in other types of deficiency than in acrodermatitis enteropathica (9 vs 88% of cases). Anorexia and/or hypogeusia is reported more frequently in the other types of deficiency (30 vs 16%). The main symptoms in acrodermatitis enteropathica vary with age. These differences in the clinical picture of Zn deficiency are discussed in relation to the degree of the deficiency (acute, subacute, or chronic; severe, mild, or subclinical). The results of the conventional laboratory tests to diagnose Zn deficiency (Zn levels in serum, urine, or hair) are reviewed. In healthy Dutch infants and children, the mean values of these levels vary by a factor of 1.6-3.0. Also, the clinical interpretation of their results is prone to errors. Therefore, we advocate the erythrocytic 65Zn uptake test. Its mean varies by 1.3. However, its reference values for different age intervals need to be established. From the comparison of the results of three conventional tests of samples taken concurrently (serum, urine, and hair) in groups of Dutch children with symptoms common in Zn deficiency (diarrhea, recurrent infection, or growth retardation), it is estimated that +/- 1% of Dutch children with minor complaints suffer from either acute or subacute Zn deficiency. Other deficiencies occur occasionally. In order to detect the individual patient with deficiency, the erythrocytic 65Zn uptake test is promising and needs to be evaluated. Therefore, we review a set of reference laboratory tests with results that alter during sequential stages of overload and deficiency. Such a scheme is advocated as a guidance for future clinical research on deficiency, and solves the problem of differentiating those conditions that identify the individual patients who need treatment by supplementation.

Changes of CSF-Cu and -Zn in children with acute lymphoblastic leukemia

In 20 Dutch children with acute lymphoblastic leukemia (ALL), Cu and Zn levels in cerebrospinal fluid (CSF) were studied during standard treatment (Protocol ALL-BFM-86/SNWLK-ALL-VII). CSF-Cu in 10 controls was 0.04 +/- 0.02 mumol/L, lower compared to values in adults. At the moment of diagnosis, CSF-Cu values were higher, 0.06 +/- 0.03 mumol/L, and during maintenance therapy lower, 0.01 +/- 0.01 mumol/L. Children with central nervous system (CNS) involvement ALL as judged by CAT Scan and EEG--in addition to cytology--showed lower CSF-Cu values compared to children without. CSF-Zn values were also measured. CSF-Zn was 0.05 mumol/L and did not vary. Cu/Zn molar ratios were increased at the onset of treatment, and decreased during maintenance therapy. The changes in CSF-Cu may follow the natural course of the disease or may relate to the success of treatment, reflecting a decrease of leukemia activity. Another explanation concerns a risk of CNS damage by low CSF-Cu causing neuron dysfunction. Conditions necessary for the interpretation of these results into a clinical strategy for followup study are outlined.