Kidney, Lungs, and Liver Flashcards
In CF which vitamins are absorbed at a lower rate?
Fat Soluble: Vitamins A, D, E, and K
What is a common prenatal finding in CF?
Echogenic bowel
Meconium Ileus (occurs in 15-20% of newborns)
What is a liver finding in CF?
Chronic liver disease and cirrhosis
What are the clinical presentations in CF?
- child with frequent ear, sinus, and pulmonary infections
- child with failure to thrive with constant or frequent diarrhea (greasy, fatty, smelly)
*adult male with infertility and severely reduced or undetectable sperm
What are the lung manifestations in CF?
Hyperinflation / barrel chest
Mucous plugging
Peribronchial thickening
Which CF variant is modified by polyT tracts and which is more severe (5T or 7T)
p.Arg117His / 5T is more severe
What is the phenotype of CFTR p.Arg117His / 5T?
Non-classic > classic
What is the phenotype of CFTR p.Arg117His / 7T?
Asymptomatic female or CAVD > non-classic
What is the CF prevalence in Ashkenazi Jewish?
1:29
What is the CF prevalence in North Americans of northern European background?
1:28
What is the CF carrier frequncy in African American?
1:61
What is the CF prevalence in Asian American?
1:118
What is the false negative rate of CF on NBS?
8%
What is Alagille syndrome?
“Paucity of bile ducts” on liver biopsy
Jaundice with increased direct bilirubin (sign of liver obstruction)
What are the findings in Alagille?
Neonatal jaundice with direct bilirubin
* Deposit in skin and cause pruritis (itching)
Progressive liver failure
Cardiac anomalies - blood vessel based (pulmonic stenosis, tetralogy of Fallot)
Butterfly vertebrae
Eye anomalies (posterior embryotoxon)
Kidney failure
What are the facial features in Alagille findings?
Broad forehead
Deep set eyes
Pointed chin
Concave or straight nasal ridge with a bulbous tip
What is the genetic cause of Alagille syndrome?
(AD)
JAG1
NOTCH2
What is the genetic cause of Gilbert syndrome?
Promoter mutation in UGT1A1
(AR)
3-7% of Americans
What is the phenotype of Gilbert syndrome?
Stress (starvation, infection, etc) brings out jaundice, sometimes fatigue
What is the genetic cause of Rotor syndrome (bilirubin)
SLCO1B1 or SLCO1B3
What is the genetic cause of Dubin-Johnson syndrome?
ABCC2 (transports conjugated bilirubin out of cells, into bile)
What are the features of Dubin-Johnson syndrome?
Rarely, neonatal cholestasis that improves
Deposits of bilirubin in liver that lead to black liver
What is the genetic cause of Crigler-Najjar syndrome?
CN1 (severe form) = complete loss of function of UGT1A1 (same enzyme as Gilbert)
What are the clinical findings in Crigler-Najjar syndrome?
Neonatal jaundice and potential kernicterus
Kernicterus = damage to basal ganglia and hippocampus
—->hypertonia, deafness, oculomotor palsy and lethargy
What are the treatments in Crigler-Najjar syndrome?
Treatment requires
*Daily phototherapy (10-12 hours per day)
*Or, liver transplant
What are the clinical findings in Primary Familial Intrahepatic Cholestasis?
Jaundice
Poor feeding and/or weight gain
Hepatosplenomegaly
Sequelae of fat-soluble vitamin deficiency—fractures (vit D), dry skin (vit E), easy bruising bleeding (vit K), night blindness (vit A)
Can lead to cirrhosis and liver failure
What are the genetic causes of Primary Familial Intrahepatic Cholestasis?
ATP8B1 (maintains plasma membrane)
ABCB11 (bile salt export pump)
ABCB4 (phosphatidyl choline excretion)
What is the biological mechanism in congenital nephrotic syndrome?
*In nephrotic syndrome, genetic defects lead to a loss of foot processes and tight interactions
*Proteins pass through into the proximal tubule
*Massive Proteinuria
What is the result of massive proteinuria in congenital nephrotic syndrome?
Failure to thrive
Body edema (proteins hold fluid in the bloodstream via oncotic pressure)
Mixed bleeding/clotting disorder due to loss of clotting factors/inhibitors
Immune deficiency (loss of immunoglobulins and complement)
What are the symptoms of Alport syndrome?
- Hearing Loss – progressive (yearly hearing exam >6y)
- Cataract
- Hematuria (Regular urinalysis)
Leads to end stage renal failure. As early as 20’s. >90% by age 40
What are the genetic causes of Alport syndrome?
X-linked (COL4A5) and two AR genes (COL4A3, COL4A).
What is the clinical phenotype in polycystic kidney disease?
Multiple bilateral renal cysts
Other cysts: liver, seminal vesicles, pancreas, and arachnoid membrane
***Aneurysms: intracranial, aorta
For brain aneurysms, always ask “does anyone have polycystic kidney disease.”
What is the age of onset of polycystic kidney disease?
For truncating mutation, will appear between ages of 15-30 years
What are the management strategies in polycystic kidney disease?
Blood pressure examination
Measurement of blood lipid concentrations– risk for ESRD
Urine studiesto detect the presence of microalbuminuria or proteinuria
Echocardiographyin persons with heart murmurs or systolic clicks
Echocardiography or cardiac MRIto screen persons at high risk because of a family history of thoracic aortic dissections
Head MRA or CT angiographyto screen persons at high risk because of a family history of intracranial aneurysms.
Note: Screening for intracranial aneurysms in individuals without a family history of intracranial aneurysms is not recommended
What are the genetic causes of poly cystic kidney disease?
(AD)
PKD1 – 78% (has pseudogene)
PKD2 – 15%
GANAB
DNAJB11
What is the difference between AD and AR poly cystic kidney disease?
AD–typically adult-onset (50% will have end stage renal disease by age 60)
AR–Neonatal/childhood onset; may detect enlarged echogenic kidneys or oligohydramnios on US
What is the genetic cause of autosomal recessive polycystic kidney disease?
PKDH1
What are the clinical features of Bardet Biedl Syndrome?
Retinal cone-rod dystrophy
Obesity
Postaxial polydactyly
Cognitive impairment
Hypogonadotropic hypogonadism and/or genitourinary malformations
Renal malformations and/or renal parenchymal disease
What is the clinical phenotype of Meckel Gruber?
Posterior encephalocele
Polydactyly
Polycystic kidneys
Perinatal lethal disorder
What is heterotaxy?
Reversal of left-right symmetry (certain structures are mirrored)
Can lead to complex heart defects
Need to evaluate chest, heart, abdomen
*Spleen scan
Can happen at different “levels”
What is the mode of inheritance of heterotaxy?
AD, AR, and XLR (ZIC3)
What is the clinical phenotype of Kartagener Syndrome?
Primary Ciliary Dyskinesia—missing dynein arms, which are responsible for ciliary movement
Frequent sinopulmonary infections
Infertility
Situs Inversus 40-50%
Heterotaxy 12% (reversal of some structures, not others)
What is the phenotype of Orofaciodigital syndrome?
Oral abnormalities
Dysmorphic facial features
Fused, extra, short, or curved fingers
What are the genes responsible for Orofaciodigital syndrome?
OFD1 (XL, AR)
What are the three main clinical features of Alagille syndrome?
Butterfly shaped vertebrae
Abnormal bile ducts
Heart defects
