Newborn Information and Courses from MediaLab, Inc.

In addition to chemical components, a few cells are also found in normal CSF. In an adult, 0 - 5 WBC/µl is considered normal. Children will have slightly higher cell counts. Up to 30 WBC/µl is within normal limits for newborns. Lymphocytes account for 60 - 100% of these cells.

Rocourt J. Jacquet C. Reilly A.: Epidemiology of human listeriosis and seafoods. International Journal of Food Microbiology. 62:197-209, 2000While rarely diagnosed prior to 1960, more than 10,000 cases of listeriosis were recorded in the medical literature between 1960 and 1982, and thousands more have been reported annually world-wide. This widespread increase in reporting is most likely due to demographic trends and changes in food production, processing and storage, especially the extended cold food chain and the ability of Listeria monocytogenes to grow at low temperaturesL. monocytogenes is a bacterium responsible for opportunistic infections, preferentially affecting individuals whose immune system is perturbed, including pregnant women, newborns, people over 65 years, immunocompromised patients, such as cancer victims, transplant recipients, people on hemodialysis and AIDS patients.Thus, the increasing lifespan and medical progress allowing immunodeficient individuals to survive, partially explains the increasing incidence of listeriosis. Moreover, L. monocytogenes is ubiquitous and can grow at temperatures as low as 0 degrees C. At this temperature growth is very slow.The expansion of the agro-food industry, the widespread use of systems of cold storage and changes in consumers demands have led to a large increase in the pool of Listeria that can cause food-borne infections.

The sites used to obtain bone marrow samples are:illiac crest (posterior, anterior)sternumspinal processestibia - (infants and newborns)The illiac crest is the most common site for bone marrow collection. Sternal aspiration can have serious or even fatal consequences if the needle penetrates the heart.

The normal M:E ratio in adults varies from 1.2:1 to 5:1 myeloid cells to nucleated erythroid cells. An increased M:E ratio (6:1) may be seen in infection, chronic myelogenous leukemia or erythroid hypoplasia. A decreased M:E ratio (<1.2-1) may mean a decrease in granulocytes or an increase in erythroid cells. M:E ratios are somewhat higher in newborns and infancy than in later childhood and in adults. It is important to note that lymphocytes, monocytes and plasma cells are not included in the M:E ratio.

ABO antibodies are not usually produced by an infant until 3 to 6 months of age. Antibodies found in the sera of newborns are almost always IgG, passively acquired from the mother. Thus, serum testing of newborns is not performed. Anti-A and anti-B titers are highest at ages 5-10 years and then they gradually decrease. Thus, in elderly patients, ABO antibodies may be difficult to detect. In patients with hypogammaglobulinemia, some leukemias, lymphomas or patients who are taking immunosuppressive drugs, the expected antibodies may be weak or even absent, reflecting the low levels of gamma globulin in the patient’s serum. As previously mentioned, these and other ABO typing discrepancies must be resolved before true ABO type can be determined.

Marcie Moore was a phlebotomist at a community hospital in Atlanta. It was her week to collect the pediatric unit and she was on her way to the room of a newborn for which she had just received orders to draw a STAT BMP (chem-7) and bilirubin. After informing the mother of the baby about the test she needed to perform, Marcie set up to perform a heel stick on the baby. Marcie chose a site on the outer edge of the heel on the bottom of the baby’s foot ( the correct area for a heel stick) and made a small incision with a Tenderfoot lancet after cleaning the site well with alcohol.She immediately began collecting the blood in the correct tube for the BMP and bilirubin. Blood flow was not strong so Marcie squeezed the baby’s foot a little to help the blood come out faster – the newborn was screaming and Marcie could tell it was making the mother uncomfortable. She wanted to hurry and get done so the mother could hold the baby.After the chemistry tech ran the blood tests on the tube, she informed Marcie that the newborn had a panic potassium level which did not coincide with the previous blood work on the newborn. Also the chemistry instrument could not perform the bilirubin due to hemolysis. Marcie was asked to recollect the specimen.

Jaundice was recognized in a day-old infant. Notice particularly the size variation (anisocytosis) of the erythrocytes on the infant's peripheral smear. What does this observation mean? Does it provide immediate information that might serve as guidance in expediting diagnosis and treatment? Note that normal-sized red blood cells, microcytes, microspherocytes, macrocytes, and nucleated red blood cells are all present. Red cell variations are expected findings in healthy neonates, but the variations here are exaggerated. Hyposplenic functional features may appear, including acanthocytes, spherocytes, and possibly Howell-Jolly bodies, especially if hemolysis is particularly vigorous. A high (3-7%) reticulocyte count is not unusual during the first three or four days after birth, however, the marrow in this jaundiced infant is proliferating vigorously in response to hemolysis. A call for more red cells is urgent. Immature red cells (in the form of nucleated red cells) and red cells with stippling of RNA (basophilic stippling) are readily identified. Red cell maturation sequence has not been totally processed in the marrow nor is all residual red cell debris removed by the spleen. In the lower photograph are reticulocytes stained by supravital stain (new methylene blue). Basophilic stippling (specks of RNA) stains with both supravital stains and with routine Wright-Giemsa stain.