The pathogenesis of PSC remains unclear but probably involves a combination of environmental factors and genetic predisposition. Notably, 70-80% of patients with PSC are comorbid with inflammatory bowel disease (e.g., ulcerative colitis or Crohns colitis), suggesting there exists a link between the two.PSC predominantly affects males (60-70%) of 30–40 years of age. The disease has an incidence is 0.4-2.0 cases/100,000 and a prevalence of 16.2 cases/100,000, making it a rare disease. Nonetheless, PSC accounts for 6% of liver transplants in the US due to its eventual progression to end-stage liver disease, with a mean transplant-free survival of 21.3 year.Though 40-50% of patients are asymptomatic, commonly reported symptoms include abdominal pain in the right upper quadrant, pruritus, jaundice, fatigue, and fever. The most common signs are hepatomegaly and splenomegaly. Prolonged cholestasis in PSC may cause fat-soluble vitamin deficiency leading to osteoporosisDiagnosis requires elevated serum alkaline phosphatase persisting for at least 6 months and the presence of bile duct strictures on cholangiogram. Unlike primary biliary cholangitis, PSC lacks a diagnostic autoantibody or reliable biomarker of disease progression. Although a liver biopsy is not required for diagnosis, the characteristic histological finding is concentric periductal fibrosis resembling onion skin.PSC is associated with increased risk of several cancers, most notably, a 400 times greater risk for cholangiocarcinoma compared to the general population. Patients with PSC also face elevated risk of pancreatic and colorectal cancer. Therefore, regular screening is recommended.No drugs are currently approved for treating PSC specifically.
Congenital cystic eye (also known as CCE or cystic eyeball) is an extremely rare ocular malformation where the eye fails to develop correctly in utero and is replaced by benign, fluid-filled tissue. Its incidence is unknown, due to the very small number of cases reported. An audit by Duke-Elder of the medical literature from 1880 to 1963 discovered only 28 cases. The term was coined in 1937 by the renowned ophthalmologist Ida Mann.Embryologically, the defect is thought to occur around day 35 of gestation, when the vesicle fails to invaginate. Dysgenesis of the vesicle later in development may result in coloboma, a separate and less severe malformation of the ocular structures. CCE is almost always unilateral, but at least 2 cases of bilateral involvement have been described. Patients may also present with skin appendages attached to the skin surrounding the eyes. Association with intracranial anomalies has been reported. Treatment
Treatment of CCE is usually by enucleation, followed by insertion of an ocular implant and prosthesis. References


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