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Serrated Polyposis Syndrome

Serrated Polyposis Syndrome Updated: 02/28/2022 © Jun Wang, MD, PhD   General features Previously called hyperplastic polyposis syndrome More common age 50-60 Increased risk for colon rectal cancer Associated with cigarettes smoking and high BMI Increased risk of colorectal cancer Clinical presentations Usually asymptomatic Endoscopic findings of large or flat polyps Key morphological features Both adenomatous and hyperplasic changes Genetic abnormalities Overall uncommon BRAF: Type1, commonly female smokers KRAS: Type 2, RNF43 Diagnostic criteria More than 5 serrated polyps proximal to the sigmoid colon, at least 2 of these are larger than 1 cm Any serrated polyps proximal to the sigmoid colon in a patient with a first degree relative with serrated polyposis syndrome More than 20 serrated polyps of any size in the colon Treatment Polypectomy, complete removal recommended Colonoscopy every 1-3 years Surgery if treatment/surveillance inadequate First ...

Chediak-Higashi syndrome

Chediak-Higashi syndrome Updated: 08/03/2020 © Jun Wang, MD, PhD General features Rare Autosomal recessive Lysosomal storage disorder Associated with primary immunodeficiency due to impaired phagocytosis Affects multiple systems Symptoms usually present soon after birth Most patients died before 10 as a result of infection or an accelerated lymphoma like phase Pathogenesis Abnormal intracellular protein transport and pigmentation Chediak-Higashi syndrome genes ( LYST/CHS1 ) mutation Abnormal organelle trafficking and fusion Defective lysosome functions Neutrophils and macrophages with normal phagocytic function but delayed fusion of phagosomes with lysosomes NK cell and T cell cytotoxicity markedly decreased due to defective exocytosis of granules Melanosome defects Clinical features Early presentations Nonpigmented skin , blonde hair, blue eyes (partial oculocutaneous albinism) Recurrent bacterial infections Coagulation defects, usually mild Aden...

Obstructive shock

Obstructive shock Updated: 06/30/2022 © Jun Wang, MD, PhD General features Reduced cardiac output due to obstruction of large vessels or heart Similar symptoms to cardiogenic shock , but different treatment Usually clinical diagnosis, based on history and clinical presentations Etiology Pulmonary vascular Pulmonary embolism Severe pulmonary hypertension Pulmonary or tricuspid stenosis, acute obstruction Mechanical Tension pneumothorax Pericardial tamponade Constrictive pericarditis Restrictive cardiomyopathy High-PEEP ventilation Vena Cava compression syndrome Cardiac mass   Increased afterload Aortic dissection Aortic valve stenosis Pathophysiology Obstruction of large vessels or heart Impaired diastolic filling Reduced cardiac preload Increased cardiac afterload Clinical presentations Non specific Presentation associated with underlying cause: cardiac mass , pneumothorax, etc Presentations of hypoperfusion: Tachycardia ...