Effect of cocaine on fetal kidney and bladder function

Infants of Mothers with Cocaine Use: Review of Clinical and Medico-Legal Aspects

Illicit drug use is a global problem that also affects pregnant women. Substance use and alcohol abuse during pregnancy may have various harmful consequences for both mothers and foetuses. Intrauterine exposure to illicit substances can be investigated through maternal reports and toxicological tests on mothers' and/or newborns' samples. While the negative effects of alcohol and opioid use on pregnancy, the foetus, and/or newborn are well established, the effects of cocaine use remain controversial. We performed a review of the literature to evaluate the current state of knowledge of the effects of intrauterine cocaine exposure on newborns' and children's long-term development and to highlight possible implications for health professionals dealing with women who use cocaine during pregnancy. Although intrauterine cocaine exposure has been associated with reduced infant measurements, no specific amount of cocaine use exerting such effects has been determined, and no long-term effects have been confirmed. The evidence of cocaine use during pregnancy justifies a clinical and social takeover of the mother and newborn without assuming that there will certainly be long-term damage related to intrauterine cocaine exposure, but also considering other possible associated factors.

Cocaine and kidney injury: a kaleidoscope of pathology

Cocaine is abused worldwide as a recreational drug. It is a potent activator of the sympathetic nervous system leading to intense vasoconstriction, endothelial dysfunction, oxidative stress, platelet activation and decrease in prostaglandins E2 and prostacyclin. Cocaine can lead to widespread systemic adverse effects such as stroke, myocardial infarction, arterial dissection, vascular thrombosis and rhabdomyolysis. In human and rat kidneys, cocaine has been associated with glomerular, tubular, vascular and interstitial injury. It is not uncommon to diagnose cocaine-related acute kidney injury (AKI), malignant hypertension and chronic kidney disease. Cocaine abuse can lead to AKI by rhabdomyolysis, vasculitis, infarction, thrombotic microangiopathy and malignant hypertension. It is reported that 50–60% of people who use both cocaine and heroin are at increased risk of HIV, hepatitis and additional risk factors that can cause kidney diseases. While acute interstitial nephritis (AIN) is a known cause of AKI, an association of AIN with cocaine is unusual and seldom reported. We describe a patient with diabetes mellitus, hypertension and chronic hepatitis C, who presented with AKI. Urine toxicology was positive for cocaine and a kidney biopsy was consistent with AIN. Illicit drugs such as cocaine or contaminants may have caused AIN in this case and should be considered in the differential diagnosis of causes of AKI in a patient with substance abuse. We review the many ways that cocaine adversely impacts on kidney function.

Nephrotoxic effects of common and emerging drugs of abuse

The kidneys can be injured in diverse ways by many drugs, both legal and illegal. Novel associations and descriptions of nephrotoxic effects of common and emerging drugs of abuse have appeared over the past several years. Anabolic androgenic steroids, illicitly used by athletes and others for decades to increase muscle mass and decrease body fat, are emerging as podocyte toxins given recent descriptions of severe forms of FSGS in long-term abusers. Synthetic cannabinoids, a new group of compounds with marijuana-like effects, recently became popular as recreational drugs and have been associated with an atypical form of AKI. 3,4-Methylenedioxymethamphetamine, commonly known as ecstasy, is a widely used synthetic recreational drug with mood-enhancing properties and a constellation of toxicities that can result in death. These toxic effects include hyperthermia, hypotonic hyponatremia due to its arginine vasopressin secretagogue-like effects, rhabdomyolysis, and cardiovascular collapse. Cocaine, a serotonin-norepinephrine-dopamine reuptake inhibitor that serves as an illegal stimulant, appetite suppressant, and anesthetic, also causes vasoconstriction and rhabdomyolysis. Recent adulteration of much of the world's supply of cocaine with levamisole, an antihelminthic agent with attributes similar to but distinct from those of cocaine, appears to have spawned a new type of ANCA-associated systemic vasculitis. This review discusses the nephrotoxic effects of these common and emerging drugs of abuse, of which both community and health care providers should become aware given their widespread abuse. Future investigation into pathogenetic mechanisms associated with these drugs is critical and may provide a window into ways to lessen and even prevent the nephrotoxic effects of these drugs of abuse and perhaps allow a deeper understanding of the nephrotoxicities themselves.

Sonography of fetal micturition

OBJECTIVE

To describe the sonographic visualization of fetal micturition and its role in the diagnosis of posterior urethral valves and hypospadias.

METHODS

This was a prospective study of 25 male fetuses (21 with bilateral pyelectasis, one whose bladder was being studied because of ureterocele and three with hypospadias), and five female fetuses (with bilateral pyelectasis). A midline sagittal scan of the fetal pelvis, perineum and external genitalia was obtained and observed continuously during fetal micturition.

RESULTS

In 19 of the 21 male fetuses and the five female fetuses with bilateral pyelectasis micturition was normal, with visualization of urinary bladder contraction, slight fluid distention of the urethra and a urinary stream from the external urethral meatus. In three male fetuses, two with bilateral pyelectasis and the one with ureterocele, the posterior urethra was normal at rest and it ballooned out during micturition, diagnostic of posterior urethral valves. In the three male fetuses with hypospadias the ventral jet of the urinary stream was visualized.

CONCLUSION

Fetal micturition can be visualized on sonography. It may be of value in the diagnosis of posterior urethral valves and hypospadias.

Fetal renal impairment

Renal function in utero deals chiefly with urine production rather than the excretion of metabolites, which are cleared by the placenta. Fetal renal impairment (FRI) in bilateral renal disease thus presents as oligohydramnios or anhydramnios; this can lead to lung hypoplasia and early neonatal death. As in the adult, FRI can be divided into prerenal, renal and postrenal causes. Causes of prerenal FRI include intrauterine growth restriction, unbalanced intertwin transfusion in monochorionic twins and maternal drug ingestion. Bilateral renal agenesis, multicystic dysplasia and both the autosomal dominant and recessive forms of polycystic kidney disease are examples of renal causes, whereas postrenal etiologies are usually caused by lower urinary tract obstruction (LUTO). When both kidneys are affected and there is severe mid-trimester oligohydramnios, the prognosis is poor. Although animal studies have shown that prolonged LUTO leads to lung hypoplasia and renal damage, and that decompression of the fetal kidney in early pregnancy restores fetal pulmonary and renal function, the value of fetal therapy such as vesico-amniotic shunting remains controversial, with a high procedure-related complication rate and a high incidence of end-stage renal failure in childhood. Fetal cystoscopic treatment of posterior urethral valves in utero may obviate some of these difficulties but remains an investigational procedure.