Neonatal problems Flashcards
What is Cretinism? Which trace element?
The child is presenting with growth retardation, deaf-mutism, gross motor delay, macroglossia, diminished reflexes, and a large abdomen with an umbilical hernia. This constellation of findings is consistent with cretinism caused by severe iodine deficiency.
Iodine’s role in humans is in the metabolism and homeostasis of the thyroid. Many diets in industrialized countries include salt that has been iodized. However, iodine deficiency is still a large health issue in many parts of the world where it has not been incorporated into the daily diet. Iodine is absorbed in the proximal small bowel and taken up into the thyroid, with excess amounts excreted through the kidneys. Its role in the body is to form components of the major thyroid hormones, T3 (triiodothyronine) and T4 (thyroxine).
Deficiency results in goiter, hypothyroidism, slowed mental development, and neonatal/infant mortality. Labs show low levels of T3 and T4 and high levels of thyroid-stimulating hormone (TSH). Fetuses, in particular, are very vulnerable to maternal iodine deficiency. The fetus is totally dependant on the mother’s production of T4 for the first 12-18 weeks of gestation. Deficiency during this time leads to cretinism, which is characterized by severe mental handicap, deafness, mutism, hypotonia, umbilical hernia, and characteristic facies including a puffy face, flattened nasal bridge, and macroglossia. Infants often feed poorly, develop gait disturbances, and are lethargic.
Neonates presenting with high fevers should suspect?
The high fever and lethargy should prompt you to rule out the most critical diagnoses. In infants who are less than 28 days old presenting with fever, there should be a high index of suspicion for sepsis and meningitis. With a high fever, an infectious workup including blood and urine culture along with a lumbar puncture should be performed. Bacterial meningitis most often occurs in children under the age of 3. Common organisms include group B Streptococcus and Escherichia coli. Enteroviruses are the most common agents of viral meningitis and occur in children of all ages, usually during the summer months. Meningitis may present with the triad of headache, high fever, and nuchal rigidity, but these may or may not be seen in infants. Empiric antibiotic therapy should be administered until bacterial meningitis can be excluded.
What is Newborn conjunctivitis? Treatment?
Newborn conjunctivitis that occurs within the first 24 hours of life is chemical reactive conjunctivitis. Timing is important in regard to newborn conjunctivitis.
The appropriate management of chemical reactive conjunctivitis is reassurance. These newborns will recover on their own in 24 to 48 hours without intervention.
What is Gastroschisis?
Gastroschisis is a congenital abnormality involving the gastrointestinal tract characterized by the evisceration of intestine through the abdominal wall, just lateral to the umbilicus. Unlike an omphalocele, the mass is edematous, dark in color, and typically appears to be covered by a gelatinous matrix of greenish material. There is no involvement of the umbilical cord. Treatment is coverage of the abdominal contents with primary staged closure.
What is Ophthalmia neonatorum?
Ophthalmia neonatorum is a term used to describe a conjunctivitis occurring within the first month after birth. The causes vary and can be differentiated by time of presentation. In the most developed countries, prophylactic erythromycin or tetracycline ophthalmic ointment is used to prevent possible infection acquired from the birth canal. However, 2% silver nitrate was previously used and may still be used in other parts of the world. Chemical conjunctivitis presents within the first 24 hours of birth and is due to exposure to any one of many chemical compounds including prophylactic ointments. It is self-limited eye redness and irritation that requires no treatment.
What is DiGeorge Syndrome?
DiGeorge syndrome (DGS) is now known to be associated with a chromosome 22q11.2 deletion syndrome. It generally will present within the first 3 days of life with low serum calcium levels and often with seizures. The facies described in the question are classic for DGS. These patients have impaired immunity related to their absence of a functional thymus. The size of the thymic shadow on imaging studies is unreliable, although it is commonly used in board questions to help with the diagnosis.
What is Polycythemia of the newborn? diagnosis? Symptoms?
Polycythemia of the newborn is relatively common and involves a central venous hematocrit (Hct) level of greater than 65%. Blood viscosity increases exponentially as the Hct level rises above 42%. Polycythemia is more common in diabetic mothers, and newborns can present with irritability, tremor, jitteriness, “ruddiness” (red color), and priapism in males. Symptoms generally begin about 2 hours after birth as this is when the hematocrit is the highest due to fluid shifts. Symptoms attributed to this disorder are felt secondary to increased blood viscosity and decreased perfusion.
The most common cause is delayed clamping of the umbilical cord with increased placental transfer of blood to the newborn. A second cause is increased intrauterine erythropoiesis due to chronic intrauterine hypoxia. This can be seen with preeclampsia or any hypertensive or vascular disorder that affects placental blood flow. Other causes would include cardiac disorders, pulmonary disorders, high altitude or smoking.
Treatment is a partial exchange transfusion (PET) using an umbilical venous catheter to reduce the central Hct level.
What is fetal hydantoin syndrome? Related to what?
The patient, in this case, is suffering from fetal hydantoin syndrome, secondary to exposure to maternal anticonvulsant therapy in utero. The most likely culprit for this condition is phenytoin. Growth retardation, microcephaly, hypoplasia of the distal phalanx of the fingers and toes, nail hypoplasia, hirsutism, cleft-lip/palate, rib anomalies, and occasionally cardiac and genitourinary anomalies are classic physical exam findings for this condition, and several are present in this patient.
The use of an anti-epileptic drug (AED) during pregnancy increases the risk of birth defects and neurodevelopmental impairments in the child, but the benefits of taking these medications during pregnancy often outweigh these risks. If a woman discontinues her AED during pregnancy, she risks status epilepticus and sudden unexpected death in epilepsy (SUDEP). The risk of the mother suffering a tonic-clonic seizure during labor and subsequent 24 hours is low but signficant at about 1%-4%. Seizures can often reduce available arterial oxygen and cause fetal hypoxia. Additionally, injuries to the mother or fetus can occur due to seizure activity.
