Evaluation of thyroid status of infants in the intensive care setting

INTRODUCTION

Previous studies report the spectrum of thyroid function abnormalities in critically-ill neonates. In this study, we evaluated the thyroid status in critically-ill neonates, and determined whether thyroid function abnormalities are more common in sick neonatal infants.

METHODS

In a prospective cohort study, 67 critically-ill infants from the Neonatal Intensive Care Unit (NICU), affiliated to Shiraz University of Medical Sciences, were entered into our study. Of all the included neonates, 33 were premature and seven were under 28 weeks of gestation. In addition to the routine thyroid-stimulating hormone (TSH)-screening (capillary specimen), serum free triiodothyronine (FT3), free thyroxine (FT4) and TSH were checked using radioimmunoassay kit twice (during critical illness and before discharge from the NICU).

RESULTS

It was observed that abnormal TSH levels (screening test) were about 40-fold higher in critically-ill neonates compared with healthy neonates, while more than four-fifths of them were detected in the second sampling done after recovery. The mean FT3 was significantly lower during the critical illness and it increased after recovery (2.537 and 3.232 pg/ml, respectively). Mean FT4 and mean TSH during the illness and after recovery did not have any significant difference.

CONCLUSION

Thyroid function abnormalities are more common in infants under intensive care and most of them manifested as "euthyroid sick syndrome"; abnormal screening tests may be due to the transient elevation of TSH during recovery from illness. Therefore, only in cases in which TSH rises more than 15-20 mIU/L or TSH remains high for a month or longer, that treatment is needed, while other cases must be followed up by serial determination of TSH and FT4. The levels of FT3 and FT4 during the illness were not affected by the duration and severity of the illness.

C-reactive protein as an indicator of aqueductal gliosis and hydrocephaly in neonatal meningitis

Serial C-reactive protein (CRP) measurements appear to be helpful in following clinical course and response to treatment of serious bacterial infections in neonates, such as meningitis, septicaemia and osteomyelitis. In previous studies, serial determination of serum CRP could detect potential complications of meningitis, such as subdural effusion, purulent arthritis and osteomyelitis, and secondary skin infection. We report an 11-day-old full-term male neonate with persistent positive CRP after treatment of bacterial meningitis, and who developed hydrocephaly at follow-up. We concluded that positive CRP was secondary to aqueduct gliosis; therefore monitoring of serum CRP levels in infants with bacterial meningitis represented useful information, not only in persistent or secondary infection, but also for destructive complications of meningitis.

Comparison of oral ibuprofen and indomethacin on closure of patent ductus arteriosus in preterm infants

Although intravenous indomethacin and ibuprofen are widely used for closure of patent ductus arteriosus in premature infants, these formulations are unavailable in the Islamic Republic of Iran. In this study of the therapeutic effects of oral treatments, 20 preterm infants were randomized to oral ibuprofen (1 x 10 mg/kg, then 2 x 5 mg/kg at 24-hour intervals) or oral indomethacin (3 x 0.2 mg/kg at 24-hour intervals). Complete ductal closure was seen in 7/10 of the indomethacin and 8/10 of the ibuprofen group. The difference was not significant. There was no reopening after the ductal closure during the hospital stay or in the follow-up visits in either group and no excessive increases in the blood urea nitrogen or serum creatinine levels were observed.

Decreased mitotic activity in the stomach, duodenum and colon of rats treated with high doses of histamine

Histamine in doses of 25, 50, 100 and 200 mg/kg significantly inhibited mitotic activity of the stomach, duodenum and colon of rats. With the above doses this effect is not dose dependent. However, only the highest dose produced acute gastric mucosal ulceration. It is suggested that decreased mitotic activity is not causally related to ulcer provocation.