Surfactant deficiency syndrome in an infant with a C-terminal frame shift in ABCA3: A case report.

Deficiency in ATP binding cassette A3 (ABCA3) causes neonatal respiratory distress, hypoxemic respiratory failure, and interstitial lung disease. ABCA3 transports phospholipids into the lamellar bodies of type II alveolar cells, a critical step in alveolar surfactant production. We report a term infant with ABCA3 surfactant deficiency syndrome with the E292V (c.875A>T; p.Glu292Val) mutation in trans with a novel C-terminal frame shift mutation (c.4938delC; p.Met1647fs). This mutation removes the final 58 amino acids and substitutes 33 incorrect amino acids. The frame shift spares membrane spanning and nucleotide binding domains, but disrupts a highly conserved C-terminal domain, which includes sequence motifs necessary for the function of human paralogs ABCA1, ABCA4, and the bacterial homolog DrrA. This observation suggests the C-terminal domain is also required for normal function of ABCA3.

Nutritional follow-up of critically ill infants receiving short term parenteral nutrition.

Few studies have tried to characterize the efficacy of parenteral support of critically ill infants during short period of intensive care. We studied seventeen infants during five days of total parenteral hyperalimentation. Subsequently, according to the clinical conditions, the patients received nutritional support by parenteral, enteral route or both up to the 10th day. Evaluations were performed on the 1st, 5th, and 10th days. These included: clinical data (food intake and anthropometric measurements), haematological data (lymphocyte count), biochemical tests (albumin, transferrin, fibronectin, prealbumin, retinol-binding protein) and hormone assays (cortisol, insulin, glucagon). Anthropometric measurements revealed no significant difference between the first and second evaluations. Serum albumin and transferrin did not change significantly, but mean values of fibronectin (8.9 to 16 mg/dL), prealbumin (7.7 to 18 mg/dL), and retinol-binding protein (2.4 to 3. 7 mg/dL) increased significantly (p < 0.05) from the 1st to the 10th day. The hormonal study showed no difference for insulin, glucagon, and cortisol when the three evaluations were compared. The mean value of the glucose/insulin ratio was of 25.7 in the 1st day and 15. 5 in the 5th day, revealing a transitory supression of this hormone. Cortisol showed values above normal in the beginning of the study. We conclude that the anthropometric parameters were not useful due to the short time of the study; serum proteins, fibronectin, prealbumin, and retinol-binding protein were very sensitive indicators of nutritional status, and an elevated glucose/insulin ratio, associated with a slight tendency for increased cortisol levels suggest hypercatabolic state. The critically ill patient can benefit from an early metabolic support.

Nutritional follow-up of critically ill infants receiving short term parenteral nutrition

Few studies have tried to characterize the efficacy of parenteral support of critically ill infants during short period of intensive care. We studied seventeen infants during five days of total parenteral hyperalimentation. Subsequently, according to the clinical conditions, the patients received nutritional support by parenteral, enteral route or both up to the 10th day. Evaluations were performed on the 1st, 5th, and 10th days. These included: clinical data (food intake and anthropometric measurements), haematological data (lymphocyte count), biochemical tests (albumin, transferrin, fibronectin, prealbumin, retinol-binding protein) and hormone assays (cortisol, insulin, glucagon). Anthropometric measurements revealed no significant difference between the first and second evaluations. Serum albumin and transferrin did not change significantly, but mean values of fibronectin (8.9 to 16 mg/dL), prealbumin (7.7 to 18 mg/dL), and retinol-binding protein (2.4 to 3.7 mg/dL) increased significantly (p < 0.05) from the 1st to the 10th day. The hormonal study showed no difference for insulin, glucagon, and cortisol when the three evaluations were compared. The mean value of the glucose/insulin ratio was of 25.7 in the 1st day and 15.5 in the 5th day, revealing a transitory supression of this hormone. Cortisol showed values above normal in the beginning of the study. We conclude that the anthropometric parameters were not useful due to the short time of the study; serum proteins, fibronectin, prealbumin, and retinol-binding protein were very sensitive indicators of nutritional status, and an elevated glucose/insulin ratio, associated with a slight tendency for increased cortisol levels suggest hypercatabolic state. The critically ill patient can benefit from an early metabolic support.

Effect of intravenous amino acids on protein metabolism of preterm infants during the first three days of life.

Twenty-three preterm infants with respiratory distress syndrome (mean birth weight 1.07 kg, SD 0.24 kg) were randomly assigned to receive glucose alone or glucose with amino acids (1.5 g.kg-1.d-1) i.v. beginning on the 1st d of life. Blood ammonia and serum urea, CO2 content, sodium, potassium, chloride, and ionized calcium concentrations were normal and did not differ between treatment groups. Nitrogen balance was significantly greater in the group that received amino acids [88 (SD 54) versus -135 (SD 45) mg.kg-1.d-1]. In 12 infants (seven, glucose-only; five, glucose and amino acids), leucine kinetic studies were also performed on the 3rd d of life. These 12 infants received a 4-h primed constant infusion of L-[1-13C]leucine. Blood and breath were collected and analyzed for [1-13C]ketoisocaproate and 13CO2, respectively. Leucine turnover and oxidation were calculated. Both leucine turnover and oxidation were significantly higher in the group receiving amino acids than in the glucose-only group [241 (SD 38) versus 164 (SD 25) mumol.kg-1.h-1 and 71 (SD 22) versus 40 (SD 17) mumol.kg-1.h-1, respectively]. In addition, the calculated rate of protein synthesis was higher in the group receiving amino acids [6.9 (SD 1.1) versus 5.0 (SD 1.2) g.kg-1.d-1]. These data indicate that the i.v. administration of amino acids (1.5 g.kg-1.d-1) to ill preterm infants beginning on the 1st d of life improves whole-body protein balance as a result of increased protein synthesis.

Modifications of surfactant phospholipid pattern in premature infants treated with curosurf: clinical and dietary correlations.

Neonatal respiratory distress syndrome (RDS) is characterized by an immature surfactant phospholipid pattern. We aimed to study the evolution of surfactant phospholipids over a 6-day period, before and after surfactant replacement therapy with Curosurf, and to investigate possible interactions with exogenous phospholipids administered during total parenteral nutrition (TPN). Seventeen premature infants with RDS were randomly assigned to receive TPN with lipids or without (glucose group). Both groups showed a similar evolution of the surfactant phospholipids. At day 6, the surfactant composition had changed towards a mature human surfactant pattern except for phosphatidylglycerol which remained low (1%), compensated for by a high phosphatidylinositol and phosphatidylserine proportion (13.3%), Phospholipid subcomponents in plasma remained unchanged in both groups. Plasma total cholesterol (151 +/- 18 vs. 113 +/- 6 mg/dl, p less than 0.05) and cholesteryl esters (172 +/- 20 vs. 113 +/- 9 mg/dl, p less than 0.01) were higher in the glucose than in the lipid group. Total calorie intake was significantly higher in the lipid group (85 +/- 4 vs. 64 +/- 6 kcal/kg.day, p less than 0.01).

Lipid-laden macrophages in tracheal aspirates of newborn infants receiving intravenous lipid infusions: a cytologic study.

Seventy-four neonates with respiratory distress syndrome had cytologic study of tracheal aspirates. Thirteen, all of whom were receiving intravenous lipid and nothing orally had abundant macrophages with foamy cytoplasm, positive for intracytoplasmic lipid by Sudan black stain, in the tracheal aspiration specimens. Cytologic surveillance of tracheal aspiration specimens may be a useful method of monitoring infants receiving intravenous lipid infusions.

Nutritional considerations for the newborn requiring intensive care.

The importance of providing nutrition for the critically ill or low-birth-weight baby is frequently over-looked in the zeal to preserve life. Unfortunately, because of this oversight, a significant factor influencing the quality of that salvaged life may be neglected. Common nutritional problems requiring a team effort have been described to emphasize the need for support by the dietitian. There is increasing evidence that what is appropriate for the term baby may not be ideal for the premature infant. Some of the recognized discrepancies are discussed, and an approach to management outlined. Through prospective evaluation, we hope to gain insight into many of the unanswered and perhaps unrecognized questions regarding nutrition for the intensive care newborn.