Pathology Notes

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 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 Hypo

Cardiogenic shock Updated: 06/23/2022 © Jun Wang, MD, PhD General features Reduced cardiac output due to severe ventricular dysfunction Adequate circulating volume Tissue hypoxia due to hypoperfusion Etiology Acute myocardial infarction: most common cause Multivessel coronary artery disease Arrhythmia Mechanic defects: septal defect, papillary muscle rupture, etc Key risk factors Older age Anterior myocardial infarction History of hypertension, diabetes mellitus, multivessel coronary artery disease, myocardial infarction Systolic BP< 120 mmHg Heart rate > 90 beats per minute Heart failure at admission EKG findings of ST-elevation and left bundle branch block Clinical presentations Presentation associated with underlying cause: acute myocardial infarction, etc Chest pain Difficulty in breathing Symptoms of shock : Tachycardia Hypotension Tachypnea Physical examination findings Distended jugular vain Coolness of skin Gallo