Pregnancy and Fetal Renal Insufficiency

Fetal Renal

There are a number of different renal impairments that can impact the fetus. Most renal impairments are related to urine production rather than elimination, because metabolites are cleared in the placenta (Vanderkeyden, Kumar & Fisk, 2003, p. 279). However, outflow problems like hydronephrosis are also possible. In some cases, congenital problems cause one kidney only to be affected. Ultrasound testing usually detects renal impairments like renal insufficiency. However effective early detection may be, there are important preventative measures that should be taken in pregnancy to reduce the chance of the fetus developing renal disease. Many of the preventative measures involve the avoidance of certain medications: both over-the-counter and prescription pharmaceuticals.

For example, Munk, von Brandis & Larsen (2010) found that Candesartan, a member of the angiotensin-receptor blockers (ARBs) family, created some fetal abnormalities and also long-term side effects including renal dysfunction and arterial hypertension in adulthood (Munk, von Brandis & Larsen, 2010). In fact, renal insufficiency is linked directly to cardiovascular disease. Animal research has revealed some connection between fetal renal mass and fetal renal insufficiency. For instance, Singh, Denton, Bertram, Jeffries, Head, Lombardo, Schneider-Kolsky, & Moritz (2009) found that elevations in plasma creatine, urea, and sodium levels are all linked with renal insufficiency in the fetus. Research also positively correlates heavy metal exposure and toxicity with renal insufficiency in animals (Steinhardt, Salinas-Madrigal, Phillips & DeMello, 1992).

Because the use of NSAIDs is relatively common, it is important to understand the connection between maternal use of nonsteroidal anti-inflammatory drugs (NSAIDs) and fetal renal insufficiency. The connection rarely manifests, but when it does, it can be fatal. There are to date "several cases of severe and sometimes irreversible renal insufficiency have been described in neonates exposed to indomethacin prenatally or in the first days of life for treatment of patent ductus arteriosus (PDA)," (Cuzzolin, Dal Cere & Fanos, 2001, p. 9). However, common NSAIDs like ibuprofen are not linked with fetal renal insufficiency (Cuzzolin, Dal Cere & Fanos, 2001). Alternative treatments to indomethacin are needed in prenatal care, in order to reduce the prevalence of fetal renal insufficiency. In all cases in which a predilection for developing renal problems exists, care should be taken when using any NSAID.

Pregnant women with certain types of cancer need to take special caution when treating their illness because of the nephrotoxic effects of certain drugs. For example, neoadjuvant trastuzumab (Herceptin (®) and carboplatin/docetaxel chemotherapy were issued to a pregnant woman in a case study by Gottschalk, Berg, Harbeck, Stressig & Kozlowski (2011). After 15 weeks of treatment, the fetus developed renal insufficiency with anhydraminios, after which the trastuzumab was discontinued. The discontinuation of the trastuzumab stabilized the amniotic fluids. Furthermore, the renal insufficiency was reversed to yield normal renal function. The findings strongly warn against the use of trastuzumab during pregnancy.