Developmental disorders

I./4.4.: Diagnostic tests

Once horsehoe kidney is found on US performed for any reason, it is essential to send urine sample for laboratory testing, including WBC and RBC count, haemoglobin, protein and glucose level. With suspected infection, a microbiological sample for swab is also essential. To investigate kidney function, basic laboratory tests are serum Na and K, creatinine, urea levels. Available imaging studies include MR or CT of the abdomen and pelvis. In children ultrasound is the first choice to reduce radiation exposure. All of these modalities are sufficient to diagnose stone formation or obstruction. Dependening on the specific clinical setting, more specialised diagnostic modalities might be required like pyelography or CTwith intrevenous contrast agent, cysto-urethrography, or urodynamic testing. According to the high incidence of vesico ureteral reflux in children with horseshoe kidney, performing a cysto-urethrography is recommended

I./4.5.: Differentiál dignosis

With todays modern imaging techniques, horseshoe kidney usually does not mean a differential diagnostic challenge. The most important is to rule out other midline retroperitoneal mass leasions like tumors of the kidney or the adrenal gland. Rarely it can be mixed with other developmental anomalies of the kidney such as ectopic kidney (the two kidneys are on the same side), or rotational abnormalities. These are rare conditions but they also predispose to urogenital complications.