Nathan J. Smith

Studies in infantile marasmus. IV. Impairment of immunologic responses in the marasmic pig.

Extract: We investigated the immunologic responses in an experimental model, the marasmic piglet. Two litters of miniature piglets of the Pitman Moore strain [46] were divided into two groups with five of the animals given normal diet and eight subjected to dietary restriction. The dietary intake of the experimental piglets was restricted to prevent further significant weight gain after the age of 35 days. The experimental animals displayed a well developed characteristic picture of severe undernutrition after 3 months of dietary restriction. Concentrations of immunoglobulins G and M (IgG and IgM) in both experimental and control pigs were similar. Antibody titers against erythrocyte A-antigen of experimental pigs were consistently lower (Table IV). Antibody responses after immunization to tetanus toxoid, sheep erythrocytes, and bacterio-phage πX 174 were remarkably similar in both groups (Tables V and VI). The experimental animals had a delay in appearance of IgG antibody after primary immunization with bacteriophage πX 174. The physiologic lymphecytosis found in the control animals was absent in the experimental group. All lymphoid organs examined in the marasmic pigs displayed marked atrophy as compared to the control animals. No tissues were identified grossly as thymus in the neck or anterior mediastinum of the experimental animals. The germinal centers of the spleen and lymph nodes were poorly formed in the experimental animals. Delayed hypersensitivity to 2,4-dinitro-fluorobenzene was demonstrated in only one of the five experimental animals while all four control animals demonstrated delayed hypersensitivity when tested at the same age. Four experimental pigs and three control pigs were immunized with BCG vaccine at 10 months of age. The mean diameter of tuberculin reaction of the experimental group was 6.5 mm; that of the controls was 27 mm when tested 4 weeks later. Both full thickness skin grafts and split thickness grafts underwent a delayed rejection in the experimental group. Lymphocyte transformation with phytohemagglutinin was studied at 6, 9, and 14 months of age in both control and experimental animals with similar results in both groups (Table VIII). Leukocytes from three experimental pigs had no increase in uptake of thymidine when tested in mixed leukocyte culture. Leukocytes from five experimental animals and three control pigs had normal leukocyte bactericidal activity against Staphylococcus aureus and Serratia marcescens. These studies provide presumptive evidence that marasmic pigs have defects in both humoral and cellular immunity. The deficiency in cellular immunity seemed greater and was manifest by thymic involution, lymphopenia, a decreased capacity to express delayed hypersensitivity, delayed homograft rejection, and absence of reactivity in the mixed leukocyte culture.Speculation: Clinical experience and recent experimental studies indicate that malnutrition decreases resistance to infection. The results presented show that cell-mediated immunity is impaired in malnutrition. Much of the immunodeficiency in malnutrition may be mediated by hyperadrenocorticism.

Hematologic studies of severe undernutrition of infancy. I. The anemia of prolonged caloric deprivation in the pig.

Extract: These studies were designed to define alterations in erythropoiesis that resulted from prolonged and controlled caloric deprivation. The caloric deprivation in the animal model chosen simulated that experienced by human infants receiving caloric intakes so restricted that infantile marasmus results.The model chosen was the young piglet receiving a diet that would support normal growth when given in adequate amounts. The intake of this diet was so restricted as to stabilize the weight of the animals at 5.0 to 7.0 kg from one to ten months of age.The studies of erythropoiesis in control piglets revealed a relatively high reticulocyte count associated with rapid growth and expansion of the red cell mass during the early months of life. The hematocrit and the hemoglobin levels increased with age, although there was a slight decrease in the total red cell mass per unit of body weight with increasing age.Iron kinetic studies were performed in normal growing pigs (table V). The mean values for plasma iron turnover (mg Fe/100 ml whole blood/24 h) were 2.07 at one month of age, 1.54 at two months of age, and 1.06 at three months of age. The mean percentage of injected Fe59 that appeared in the circulating erythrocytes seven days after injection was 95 at one month, 82 at two months, and 76 at three months of age. These findings are consistent with the presence of a decreasing rate of erythropoiesis and hemoglobin synthesis accompanying the relative decrease in growth rate with progressive age.Animals maintained on a very restricted caloric intake were found to have immediate alterations in erythropoiesis (table VI). Plasma iron turnover in these animals was 2.26 mg on the second day following dietary restriction and only 1.28 mg when measured four days after dietary restriction. After ten days, the value was reduced to 0.88 mg. A prompt decrease in urinary erythropoietin excretion was detected during this time and persisted throughout the period of observation while the animals were on the restricted diet (fig. 3). The appearance of iron in circulating erythrocytes seven days following the injection of Fe59 was found to be 100% when iron was given two days following dietary restriction. When the isotope was given four days following initiation of the restricted diet, 86.5% appeared in the circulating erythrocytes at seven days. A further decrease to 52% was observed in a study initiated ten days after dietary restriction.The alterations in erythropoiesis demonstrated by iron kinetic studies were also reflected by a decrease in the reticulocyte count and by an increase in the myeloid: erythroid ratio in bone marrow examined serially.The measurement of the Cr51 total erythrocyte mass prior to dietary restriction was 24.8 ml/kg (fig. 8). After thirty days on restricted caloric intake, the mean value was 25.8 ml/kg. Erythropoiesis, although decreased, continued at a rate sufficient to maintain a constant red cell mass during this immediate period of caloric restriction.Prolonged caloric deprivation produced a decline in hemoglobin levels and hematocrit in the experimental pigs (fig. 7). The reticulocyte count fell from the level of 5.6 to 1 % or less during the period of dietary restriction and was maintained at the low level of 1 % throughout the period of observation. Cr51 erythrocyte mass, which was maintained at a constant level during the first thirty days of dietary restriction, showed thereafter a progressive fall throughout the period of undernutrition and paralleled the fall in hematocrit (table VIII) . Levels of protein, folate, and iron in serum were maintained within the normal range throughout the period of caloric deprivation.Studies performed in pigs after five to seven months of dietary restriction found plasma iron turnover to be lower than that observed in the control animals and essentially the same as that observed after ten days of diet restriction. After six months of diet restriction, iron utilization was reduced to a maximum utilization of 3 1 to 64 % (fig. 9).After a period ofseven to eight months of dietary restriction, five animals were offered diet ad libitum. Within three to eight days, a prompt increase in erythropoietin excretion was seen; the reticulocyte count increased and, by six days after ad libitum feedings, had reached levels characteristic of normal, rapidly growing pigs. An increase in plasma iron turnover and per cent utilization of iron was measured ten days after initation of ad libitum feedings, and the myeloid: erythroid ratio reflected an increase in erythroid precursors soon after starting ad libitum feedings.The hematocrit decreased promptly after initiation of the ad libitum diet. The lowest level was reached in five days. The Cr51 total red cell mass had increased during the period of falling hematocrit, and the total plasma volume had also greatly increased at this time. The early fall in hematocrit was thus due to the increase in the plasma volume, rather than to any decrease in the circulating erythrocyte mass.Speculation: The availability of an animal model of prolonged caloric deprivation uncomplicated by infection, parasitism, or blood loss has demonstrated that caloric deprivation per se will result in a modest reduction in hematocrit and hemoglobin concentration that is paralleled by a reduction in the total circulating red cell mass. Such animals fail to demonstrate a deficiency of specific nutrients essential for normal erythropoiesis. The finding by others that caloric deprivation may be associated with a hypometabolic state suggests that anemia accompanying caloric deprivation may not be a primary consequence of inadequate nutrition but, rather, a reflection of an adaptive reduction in hemoglobin concentration in the face of a reduced demand for oxygen transport.

THE EFFECT OF TRIETHYLENE THIOPHOSPHORAMIDE IN THE TREATMENT OF LEUKEMIA AND CERTAIN LYMPHOMAS IN INFANTS AND CHILDREN

Summary 1. The results of treatment with a thio derivative of triethylene phosphoramide of twenty-one children with leukemia, lymphosarcoma, and Hodgkins disease have been presented. 2. This agent would appear to be of use in the temporary control of lymphosarcoma and chronic forms of leukemia. 3. The drug is contraindicated in the therapy of acute leukemias of childhood. 4. The toxic manifestations from overdosage of the agent have been limited to bone marrow depression. If this serious complication is to be avoided therapy must be guided by careful clinical and laboratory evaluation of the patients during the course of treatment. 5. This agent appears to have the advantage of a wider margin of safety between the toxic and therapeutic doses than do other ethylenimine derivatives currently available.

Hematologic studies of severe undernutrition of infancy. II. Erythropoietic response to phlebotomy by calorie-deprived pigs.

Extract: These studies have determined the erythropoietic response of the chronically calorie-deprived pig to the hypoxic stress of phlebotomy. Three animals were maintained on diets sufficiently restricted to prohibit weight gain from twenty-one days to six months of age. The animals were anemic, with hematocrit values of 35%, and were subjected to controlled phlebotomy of one-third the total erythrocyte mass. During a subsequent two-month period, two of the animals were given a caloric diet ad libitum and a seven-fold increase in weight, accompanied by active erythropoiesis and an increase in hematocrit, was observed. Phlebotomy studies were repeated after the period of ad libitum feeding. The erythropoietic response to phlebotomy was evaluated in both the undernourished and the rehabilitated pigs by study of erythropoietin excretion, circulating reticulocyte numbers, iron kinetics, Cr51 total RBG mass, bone marrow morphology, and changes in serum iron concentration.When measured on day 2 preceeding phlebotomy, the calorie-deprived animals had very low concentrations of urinary erythropoietin (0.06 U/24 h) which, following blood loss, promptly increased to a concentration of 2.0 U/24 h. A similar prompt response was seen in the rehabilitated animals (fig. 1). Prior to phlebotomy, plasma iron turnover was < 1.0mg/100 ml whole blood/24 h and promptly increased to 1.5–2.0 mg/100 ml whole blood/24 h by four days after phlebotomy (fig. 2). There was a marked increase in iron utilization for erythrocyte production when measured six days following phlebotomy (fig. 3). A decrease in the myeloid: erythroid ratio of the marrow accompanied these other evidences of increasing erythropoiesis (fig. 4). The degree of response in the calorie-deprived and in the rehabilitated animals was similar. The calorie-deprived animals had a higher reticulocyte response to phlebotomy than the animals fed ad libitum, but reestablished the prephlebotomy hematocrit no more rapidly (figs. 5 and 6). The higher reticulocyte counts in the undernourished pigs was shown to be related to less mature reticulocytes entering the circulation following the bleeding stress, reflecting a greater degree of marrow ‘shift’ (fig. 8).Calculation of total erythrocyte production in response to phlebotomy under conditions of severe caloric deprivation and ad libitum feeding demonstrates that a comparable response occurred under both experimental conditions.Speculation: These studies support the hypothesis that anemia accompanying chronic caloric deprivation in the pig is not caused by a primary lack of essential nutrients, but represents an adaptive response to the decreased metabolic needs of the chronically undernourished organism. It is likely that the moderate anemia sometimes seen in marasmic infants is due to a similar mechanism. If such is the case, therapeutic measures such as blood transfusions and administration of various hematinics directed primarily at altering this adaptive phenomenon would appear contraindicated in the management of the marasmic infant.

Granulocyte responses of children to bacterial endotoxin

Thirty infants and children with various diseases and 19 controls were given intravenous injections of a purified bacterial endotoxin to study their bone marrow granulocyte reserves. No serious reactions or sequellae were seen with the dosages employed. A significant increase in circulating granulocytes was observed in all hematologically normal children. The range and nature of the responses were compared to children with various diseases. Poor-to-absent granulocytic responses were seen in children with aplastic anemia and acute leukemia. With certain recognized limitations in interpretation, the test would appear to be a safe and useful adjunct for the study of marrow function in children.

Bone marrow failure in pediatric patients: I. Cortisone and testosterone treatment*

Nine children with acquired aplastic anemia and four children with constitutional aplastic anemia were treated for 1 to 19 months with cortisone and testosterone. Five of the nine children in the acquired group demonstrated hematologic improvement which has been sustained without therapy for 12 to 36 months. Improvement would appear to be permanent in these children. While the four children with constitutional aplastic anemia demonstrated initial hematologic improvement, prompt relapse occurred following cessation of therapy and necessitated maintenance hormonal therapy. Growth performance was not altered during the course of therapy.

Iron as a therapeutic agent in pediatric practice.

Summary 1. Iron salts have a well-established role in the prevention and treatment of iron deficiency states. 2. Iron should be administered as a simple iron salt, in divided doses, and for adequate periods of time. Adjuncts such as cobalt, folic acid, molybdenum, copper, and ascorbic acid are of no practical use in the treatment of iron deficiency. 3. In rare instances in which chronic gastrointestinal disease prohibits the absorption of oral iron, iron-dextran can be given intramuscularly. In other situations it is no more effective than iron salts given by mouth. 4. Specific diagnosis is the keystone to successful and safe iron therapy. Chronic, toxic iron overload is a potential danger in any patient being given iron in the absence of a proper diagnosis. 5. The anger of accidental, acute iron poisoning in small children must be appreciated by any family in which medicinal iron is to be used.

Willful Trauma To Young Children a Challenge To the Physician

were Supported by a Grant from The Gerber Baby Food Fund. UNTIL recently, little attention or investigation was given to the various medical, social, and legal implications related to the willfully traumatized child. In the past year or so, however, lay publications, medical journals, social work journals, government bulletins, and a standard pediatric textbook have been strongly emphasizing the apparently growing number of infants and young children who

56 The Adaptive |[lsquo]|Anemia|[rsquo]| of Severe Protein Calorie Malnutrition |[lpar]|Marasmus|[rpar]|

A reduced hemoglobin concentration with normocytic, normochromic erythrocytes commonly cocurs in severely marasmic infants. Severe marasmus has been produced in 20 piglets by feeding a balanced but restricted diet to stabilize their weight at 5 to 7 kg for up to 9 months. Eight additional piglets served as controls. Clinical, autopsy and biochemical observations show the similarity of this animal model to marasmus previously studied in human infants. Red cell indices, marrow morphology, transferrin iron, marrow iron stores and DFP32 erythrocyte life span are all normal and fail to indicate the presence of any specific nutritional deficiency that alters the production or survival of erythrocytes in marasmus. In spite of these findings the animals have a persistent but not progressive reduction of hemoglobin concentration (10 to 11 gms % compared to 15 to 16 gms % normal). Cr51 studies reveal a red cell mass deficit (16.5 ml/kg in 7 months, 6 kg pigs compared to 25 ml/kg in normal 6 kg pigs). The animals were stressed by controlled phlebotomy. A prompt erythropoietic response occurred with return to the prebleeding hemoglobin level. Small increases of food intake were consistently and rapidly followed by increased erythropoiesis as measured by reticulocyte counts, M:E ratio, and iron59 kinetic studies. On the basis of these results it is proposed that the impaired erythropoiesis in marasmus is not caused by a specific nutritional deficiency. The ‘anemia’ that is present represents an adaptation to the reduced metabollic demands of these undernourished subjects. The proliferative activity of the erythropoietic tissue may provide a sensitive measure of response to nutritional rehabilitation. (APS)

Hematologic Disorders in the Newborn

Hematologic disorders can seriously threaten the welfare of newborn infants. A comparatively small loss of blood may be a life-endangering hemorrhage in a small infant. The susceptibility of the newborn s central nervous system to damage by bilirubin adds a most serious threat to a hemolytic crisis. Disorders of the blood in the newborn often are difficult to diagnose, and prompt emergency treatment must be administered if permanent residual damage is to be avoided.