Multicystic dysplastic kidney

In most cases renal agenesis can be regarded as a manifestation of a spectrum including hydronephrosis - cortical cysts (Potter type IV) - hypo-plastic/dysplastic or multicystic dysplastic kidneys - and renal agenesis depending on the time of the interaction of a disruption (e.g. obstruction). Dysplastic kidneys often vanish during life completely. 

The kidney functions poorly and the condition usually necessitates a nephrectomy. The condition may mimic a giant multicystic dysplastic kidney. 

Differential diagnosis of UPJ obstruction should include multicystic dysplastic kidney (MDK), infundibular stenosis, and UVJ obstruction. This differential diagnosis is easy in most cases. In IVIDK, no... 

Ureterocele (ucele) represents cystic dilatation of the intravesical segment of the ureter. It is more common with duplex kidneys. When it is associated with a single system, the ucele is commonly intravesical. An ectopic ucele may also be associated with a multicystic dysplastic kidney (Fig. 5.32). On US, the ucele appears as a cystic structure within the bladder that is connected with the ureter (Fig. 5.33) the upper urinary tract is not necessarily obstructed or dilated. On IVU, after injection, the ucele appears as a filling defect within the bladder, especially on early films, and it opacifies progressively (Fig. 5.34). 

Fig. 5.32. Right side ureterocele associated with a multicystic dysplastic kidney mild dilatation of the left collecting system (30-s view of an IVU)...

The treatment is similar to that for ucele in duplex kidneys depending on the degree of secondary obstruction (Gonzales 1992). It is worth noting that a ucele may be associated with a multicystic dysplastic kidney. 

Hattery R, King BF (1995) Technique and application of MR urography. Radiology 194 25-27 Helin 1, Persson PH (1986) Prenatal diagnosis of urinary tract abnormalities by ultrasound. Pediatrics 78 879-883 Hendry PJ, Hendry GMA (1991) Observations on the use of Doppler ultrasound in multicystic dysplastic kidneys. Pediatr Radiol 21 203-204... 

Sweeney WE, Chen Y, Nakanishi K et al (2000) Treatment of polycystic kidney disease with a novel tyrosine kinase inhibitor. Kidney Int 57 33-40 Srivastava T, Garola RE, Hellerstein S (1999) Autosomal dominant inheritance of multicystic dysplastic kidney. Pediatr Nephrol 13 481-483... 

Contralateral VUR may be present in about 10%-20% of patients with multicystic dysplastic kidney (Fig. 11.29). VUR is also present in a significant number of other uropathies, i.e., horseshoe kidney, crossed fused kidney, UPJ, and UVJ obstruction. Therefore, in any anomaly of this type, a VCU should be advised for a complete workup (Atiyeh et al. 1992 Ring et al. 1993 Song et al. 1995 Avni et al. 1997 Cascio et al. 1999). 

Multicystic kidney or multicystic dysplastic kidney (MCDK) (Fig. 12.5) may occasionally cause confusion with severe unilateral RPD. In MCDK there is no... 

Fig. 12.5. Multicystic dysplastic kidney, US. Antenatal diagnosis of hydronephrosis. On the lower image there is a clear multicystic kidney, but the upper image shows how one may experience difficulty in distinguishing between a large renal pelvic dilatation and a multicystic kidney...

Multicystic dysplastic kidney disease is by far the most common cystic renal disease that can be detected in utero. The condition is usually unilat-... 

Renal tumors are rare. They can be cystic, solid or of mixed type. Multiple cystic masses are more likely to correspond to a multicystic dysplastic kidney that can affect only part of a duplex kidney. Differential... 

For all other anomalies, especially multicystic dysplastic kidney, renal ectopia, or unilateral agenesis, the workup should also include US and eventually a VCU in order to detect ipsi- or contralateral VUR, which would require prophylactic chemotherapy (AxiYEHetal. 1993 Flack and Bellinger 1993 Selzman and Elder 1995 Ismaili et al. 2005). Also of interest is to search for associated genital anomalies on pelvic ultrasound (Table 13.5) (Riccabona et al. 2006). 

Once the diagnosis of multicystic dysplastic kidney (MDK) appears highly probable (on the basis of the neonatal US examination and on the lack of... 

The differential diagnosis of multicystic renal masses also includes WT with cyst formation due to hemorrhage and necrosis, cystic clear cell sarcoma, cystic mesoblastic nephroma, cystic renal cell carcinoma, multicystic dysplastic kidney and segmental multicystic dysplasia (Agrons et al. 1995). 

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