Preauricular sinuses and preauricular cysts are two common congenital malformations. Each involves the external ear. The difference between them is that a cyst does not connect with the skin, but a sinus does. Frequency of preauricular sinus differs depending the population: 0.1–0.9% in the US, 0.9% in the UK, and 4–10% in Asia and parts of Africa.Preauricular sinuses are inherited features, and frequently appear next to both ears. Preauricular sinuses can be associated with other defects that are not visible, one example being branchio-oto-renal syndrome. Presentation
Complications
Occasionally a preauricular sinus or cyst can become infected. Most preauricular sinuses are asymptomatic, and remain untreated unless they become infected too often. Preauricular sinuses can be excised surgically, but often present a high risk of recurrence. Causes
Preauricular sinuses and cysts result from developmental defects of the first and second pharyngeal arches. This and other ear malformations are sometimes associated with renal anomalies. In rare circumstances these pits may be seen in genetic conditions such as branchio-oto-renal syndrome; however these conditions are always concurrent with other health concerns. Treatment
Courses of treatment typically include the following:
Surgical excision is indicated with recurrent fistular infections, preferably after significant healing of the infection. In case of a persistent infection, infection drainage is performed during the excision operation. The operation is generally performed by an appropriately trained specialist surgeon e.g. an otolaryngologist or a pediatric Surgeon. The fistula can be excised as a cosmetic operation even though no infection appeared. The procedure is considered an elective operation in the absence of any associated complications.
Urinary tract obstruction is a urologic disease consisting of a decrease in the free passage of urine through one or both ureters and/or the urethra. It is a cause of urinary retention. Complete obstruction of the urinary tract requires prompt treatment for renal preservation. Any sign of infection, such as fever and chills, in the context of obstruction to urine flow constitutes a urologic emergency. Causes
Causes of urinary tract obstruction include:

Bladder stone and renal stone
Benign prostatic hyperplasia
Obstruction as a congenital disorder. Congenital urinary tract obstruction
Urinary tract obstruction as a congenital disorder results in oligohydramnios which in turn can lead to the Potter sequence of atypical physical appearance. Pulmonary hypoplasia is by far the main cause of death in the early neonatal period for children with congenital lower urinary tract obstruction.Fetal surgery of congenital lower urinary tract obstruction seems to improve survival, according to a randomized yet small study. Sitting voiding position
A meta-analysis on the influence of voiding position on urodynamics in healthy males and males with LUTS showed that in the sitting position, the residual urine in the bladder was significantly reduced. The other parameters, namely the maximum urinary flow and the voiding time were increased and decreased respectively. For healthy males, no influence was found on these parameters, meaning that they can urinate in either position. Diagnosis
Treatment
Treatment depends on the underlying cause of the obstruction and the severity of the symptoms. References


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