Kidney Replacement Therapy in Low Birth Weight Preterm Newborns.

Managing newborns with kidney failure is a complex undertaking; even under ideal circumstances, dialysis is technically challenging and available therapies are designed for adults. These issues are exacerbated in smaller newborns, and intervention has traditionally not been offered in those below a certain weight threshold. Ethical concerns abound and patients deemed too small for dialysis are typically transitioned to comfort or palliative care. However, many of these neonates are otherwise healthy and would be considered survivable if kidney replacement therapy were available. To challenge the existing paradigm, we present 7 preterm, low birth weight neonates with end-stage kidney disease who were successfully managed using an innovative approach to kidney replacement therapy. These newborns had a median gestational age of 32 weeks (interquartile range [IQR], 32-35) and a median birth weight of 1.58 kg (IQR, 1.41-2.01). Kidney replacement therapy was initiated at a median age of 16 days (IQR, 1.5-40) and a weight of 1.85 kg (IQR, 1.57-2.1). Five of the 7 newborns (71%) survived to hospital discharge. Kidney replacement therapy was provided using 3F and 4F single lumen catheters and a modified ultrafiltration device. Patients experienced excellent metabolic control, and fluid homeostasis was achieved in the first week of life. Furthermore, survivors experienced physiologic weight gain and linear growth throughout their hospitalization. These findings, although preliminary, are encouraging for our smallest patients with kidney failure and suggest that survivability thresholds should be reexamined. At a minimum, neonatologists should be aware that novel approaches exist and may be considered for these challenging patients.

Effects of nonylphenol on the gonadal differentiation of the hermaphroditic fish, Rivulus marmoratus.

Nonylphenol (NP) is an estrogenic degradation product of alkylphenol polyethoxylate surfactants. In this study, the effects of NP on gonadal differentiation and development in Rivulus marmoratus (Osteichthyes, Cyprinodontiformes), a self-fertilizing, hermaphroditic species, were examined. Starting at hatching, fish were exposed to 150 or 300 microg 1(-1) NP (nominal concentrations) in a static system with daily renewal. The measured concentration of NP in the test water decreased rapidly; half-life was 8.0 h. After 60 d of exposure to NP, fish were kept in uncontaminated water for 20 d and were then preserved for histological examination. No fish exposed to 300 microg l(-1) NP (N=8) and only two of nine fish exposed to 150 microg l(-1) NP developed testicular tissue, compared with nine of 13 water-control fish and five of nine solvent-control fish. Oogenesis was also significantly inhibited by NP. None of the fish exposed to 300 microg l(-1) and only two of nine fish exposed to 150 microg l(-1) NP had vitellogenic oocytes, compared with seven of 11 water-control fish (not including males) and six of nine solvent-control fish. Dysplasia of the gonadal lumen also occurred in fish exposed to 300 microg l(-1) NP. These changes, including testicular agenesis, have not been previously reported in fish exposed to NP.