Diseases Flashcards
What disease is characterized by a child that has to use both arms to push oneself up to stand? What are other features of the disease including inheritance and physical features?
Duchenne muscular dystrophy
Frame-shift mutation that is X-Linked
Person also has Pseudohypertrophy of the calves from fatty replacement of muscle
Tends to onset in early childhood and have a faster progression than Becker MD
Types and differences between muscular dystrophies
There are two types of muscular dystrophy–Duchenne and Becker. They are different mutations of the same gene leading to atrophy of skeletal and cardiac muscle. Cardiomyopathy eventually develops leading to CHF and death. Both happen almost exclusively in males. X-linked
Duchenne: unset in early childhood and faster disease progression, live into 20s
Becker: onset later in adolescence, milder symptoms and slower progression, live into 40s
Inheritance pattern for Hemophilia A & B
X-linked recessive
Hemophilia A vs B
Hemophilia A: factor VIII deficiency
Hemophilia B: “Christmas Disease” factor IX deficiency
Both are X-linked recessive disorders and therefore affect primarily males
Cystic Fibrosis:
Inheritance Pattern
Etiology
Organs affected
Autosomal Recessive
Gene mutations => dysfunctional CFTR protein that usually transports Cl ions
Affects mostly the lungs => chronic infections from thickened mucus
Also affects the pancreas => insufficiency => malabsorption, fatty stools, etc.
Causes male infertility by causing congenital malformation of the Vas Deferens
Also affects liver, kidney, intestines
Hemochromatosis:
Any condition causing an accumulation of iron in the body
Usually a hereditary condition: autosomal recessive
Marfan’s Syndrome:
Inheritance
Autosomal Dominant
Neurofibromatosis:
Inheritance
Characteristic lesions
Autosomal Dominant
Cafe-au-Lait spots, neural tumors
Fabry Disease:
Inheritance
Description
X-linked
Lysosomal storage disease
Enzyme deficiency causes accumulation of a glycolipid in vessels and organs causing altered function
Rhabdomyoma
Benign tumor of striated muscle
Commonly in the heart–most common primary tumor of the heart in infants and children
Can also occur commonly in the tongue
Crigler Najjar
UDP-glucuronyl transferase enzyme is absent
This is a necessary enzyme to conjugate bilirubin in the liver
Unconjugated hyperbilirubinemia
Gilbert Syndrome
UDP-glucuronyl transferase enzyme is deficient or low
This is a necessary enzyme to conjugate bilirubin in the liver
Unconjugated hyperbilirubinemia
Rotor Syndrome
Asymptomatic conjugated hyperbilirubinemia
Defective liver uptake and excretion of bilirubin pigments
Dubin-Johnson Syndrome
Chronic conjugated hyperbilirubinemia
Defective canalicular protein causes impaired biliary excretion of bilirubin
Describe Syphilis:
Causative agent
Progression of disease
Tests to diagnose
Agent: Treponema pallidum, spirochete
Disease: 3 stages:
- Primary: painless chancre on genitals
- Secondary: systemic, lesions on palms and soles and body, wart-like lesions on genitals ( condylomata lata)
- Tertiary: Gummas (chronic granulomas), neuro syphilis, prostitute’s pupil (accommodates, but doesn’t react to light)
- Congenital: transplacental after first trimester, rhagades (linear sores at corners of mouth), snuffles (nasal discharge), notched teeth, CN VIII deafness
Tests: FTA-ABS best test, VDRL/RPR are serological tests that are nonspecific, but can work
What are the classic signs and symptoms of pancreatic adenocarcinoma?
Weight loss, epigastric pain radiating to the back, jaundice, elevated amylase and lipase and alk phos
Tumor markers for this cancer are CA 19-9 and carcinoembryonic antigen (CEA) (CEA less specific)
Tumor more commonly in pancreatic head, a very aggressive tumor that often has metastasized by the time it is diagnosed,
Patient may also have Trousseau’s Syndrome which is a migratory thrombophlebitis that will appear with swollen, red, tender limbs and then spontaneously resolve
Trousseau Syndrome
Migratory thrombophlebitis
Presents with red, swollen limbs that are tender to palpation
Often associated with pancreatic adenocarcinoma
Tay-Sachs Disease
Autosomal recessive disorder found commonly in Ashkenazi Jews and Pennsylvania Dutch and Louisiana Cajuns
Deficient hexosaminidase A enzyme prevents proper metabolism of sphingolipids causing a buildup of these lipids in neural tissue leading to progressive deterioration of nerve cells leading to decreasing mental and physical abilities.
The most common form begins at age 4-8 months and causes death by age 4
Characteristic sign is a cherry red spot on the macula of the retina
No hepatosplenomegaly is present
Lysosomes have onion skin
Gaucher disease
Most common of the lysosomal diseases
Autosomal recessive
Lacks beta-glucocerebrosidase leading to accumulation of glucocerebroside
Symptoms include aseptic necrosis of the femur and HSM
Fabry disease
X-linked recessive lysosomal storage disease
Lacks alpha-galactosidase A enzyme causing accumulation of ceramide trihexoside
Presents with peripheral neuropathy, cardiovascular and renal disease
Niemann-Pick disease
Autosomal recessive disease
Lack sphingomyelinase
Progressive neurodegeneration and cherry red spot on macula
Hepatosplenomegaly and foam cells
Thrombotic Thrombocytopenic Purpura (TTP)
Classic Sx remembered by FAT RN: Fever Anemia (microangiopathic) having schistocytes in blood smear Thrombocytopenia Renal failure Neurologic disturbances
Caused by an antibody against ADAMTS13 which is a metalloprotease responsible for cleaving vWF multimers into smaller pieces. Accumulation of these multimers leads to platelet microaggregates which block small blood vessels throughout body.
Treatment by plasma exchange to remove the antibody
Schizophrenia
Etiology: Increased Dopamine levels in the brain
SSx: Auditory hallucinations, grandiose delusions, disorganized speech with loose associations, catatonic behavior, disorganized behavior (these are the positive symptoms)
Negative Sx: 5 A’s–Flat affect, Avolition, Alogia, Anhedonia, poor Attention
Decreased dopamine in the prefrontal cortex may cause the negative Sx and may explain why antipsychotic meds don’t relieve these Sx.
What are the effects of increased or decreased serotonin in the brain?
Increased serotonin can lead to aggression
Decreased serotonin can lead to depression
What neurotransmitter levels are off in Parkinson’s disease?
Low dopamine levels
Acromegaly
Caused by a pituitary adenoma that produces too much GH.
Patient will see a gradual increase in size of hands and feet, coarsening of features, large tongue, deepening of furrows, deepening of voice
Diagnosis is by measuring levels of IGF-1, and doing a glucose tolerance test to see if GH levels decrease with a glucose load.
Preferred treatment is surgery. Octreotide can be used in the meantime. It acts like somatostatin to counter the actions of GH.
Addison Disease
Condition of steroid deficiency
SSx: hypotension, fatigue, skin hyperpigmentation
Treatment: glucocorticoid and mineralcorticoid replacement as necessary
Syndrome of inappropriate ADH secretion
Occurs in head trauma or lung small cell cancer
Causes excess water resorption
5 alpha-reductase deficiency
These individuals are genetically male, but have ambiguous genitalia at birth and are raised as females until puberty when an increase in testosterone will suddenly cause the growth of a penis.
Enzyme is needed to convert testosterone to DHT
