6 Flashcards
diagnostic test of DMD
DNA peripheral blood analysis and/or immunohistochemical detection of abnormal dystrophin on a muscle biopsy tissue section, elevated serum creatine kinase (CK) (also elevated in many female carriers of the gene)
DMD genetics?
disease mechanism at the genetic level ?
X-linked recessive trait.
An out of frame mutation at the Xp21.2 locus encodes for an aberrant form of the protein dystrophin, which normally functions to stabilize the muscle membrane proteins.
classic signs of Duchenne muscular dystrophy (DMD):
waddling gait and progressive proximal muscle weakness, enlarged calves, toe walking on ambulation, increasing lumbar lordosis (gluteal weakness), frequent falling, difficulty climbing stairs,
other complications of DMD
Cardiomyopathy (EKG findings on the precordial leads of tall R waves on the right and deep Q waves on the left can be seen)
Nonprogressive intellectual impairment is common (mean IQ 80); brain atrophy can be seen on brain CT
respiratory failure, wheelchair dependent, scoliosis
Becker MD
an X-linked recessive disease caused by a genetic in-frame mutation at the Xp21.2 locus, which results in a similar, but less severe disease with later onset than DMD.
muscular dystrophy treatment
Orthopedic intervention, including bracing and tendon lengthening
Physiotherapy may delay the onset of contractures but can hasten muscle degeneration
Prednisone (optimal dosing 0.75 mg/kg/d) age 5 and older
All DMD patients have some degree of ? so routine evaluation is required
may be responsive to ?
cardiomyopathy
Early cardiac dysfunction may be responsive to digoxin
what is common cause of death in DMD
respiratory failure
Another common form of MD is ? the second most common type of MD in the United States
genetics? presentation?
myotonic muscular dystrophy, autosomal dominant trait
inverted V-shaped upper lip, thin cheeks, and wasting of the temporalis muscles. The head is abnormally narrow, and the palate is high and arched
progressive challenges in walking, speech difficulties, GI tract problems, endocrinopathies, immunologic deficiencies, cataracts, intellectual impairment, and cardiac involvement.
rales
Wet or “crackly” inspiratory breath sounds due to alveolar fluid or debris; usually heard in pneumonia or CHF
staccato cough often heard in ?
pertussis and chlamydial pneumonia (Coughing spells with quiet intervals)
pleural effusion
Fluid accumulation in the pleural space; may be associated with chest pain or dyspnea; can be transudate or exudate depending on results of fluid analysis for protein and LDH; origins include cardiovascular (CHF), infectious (mycobacterial pneumonia), and malignant (lymphoma)
pulse oximetry
Noninvasive estimation of arterial oxyhemoglobin concentration (SPO2) using select wavelengths of light.
CXR findings in pneumonia
single or multilobar consolidation (pneumococcal or staphylococcal pneumonia), air trapping with a flattened diaphragm (viral pneumonia with bronchospasm), perihilar lymphadenopathy (mycobacterial pneumonia) an interstitial pattern (mycoplasmal pneumonia), pleural effusion and abscess formation (bacterial infection)
60% of pediatric pneumonias are ? in origin, with ? topping the list.
? run a close second
bacterial, pneumococcus topping the list
Viruses
viruses implicated in ped pneumonia
respiratory syncytial virus [RSV], adenovirus, influenza, parainfluenza, enteric cytopathic human orphan [ECHO] virus, Coxsackie virus)
diagnosis and treatment usually are directed by ? in pediatric pneumonia
pt s/s, physical and radiographic findings, and age as routine culture of nasopharynx and sputum is typically not performed
pneumonia bugs 1st few days of life
Enterobacteriaceae and GBS
other possibilities include Staph, S. pneumo, and Listeria
abx for newborn with pneumonia
ampicillin with either gentamicin or cefotaxime
During the first few months of life, ? is a possibility, particularly in the infant with staccato cough and tachypnea
Chlamydia trachomatis
with or without conjunctivitis or known maternal chlamydia history
may have eosinophilia, and bilateral infiltrates with hyperinflation on chest radiograph
treatment for chlamydial pneumonia
erythromycin, sulfisoxazole (the latter only in infants older than 2 months)
Viral etiologies 1st few days of life include ?
HSV, enterovirus, influenza, and RSV; of these, HSV is the most concerning and prevalent viral pneumonia in the first few days of life, tx with IV acyclovir
Beyond the newborn period and through approximately 5 years of age, viral pneumonia is common; common offenders?
Bacterial etiologies?
adenovirus, rhinovirus, RSV, influenza, and parainfluenza
pneumococcus and nontypeable Haemophilus influenzae.
diagnostic tests for viral pneumonia
Nucleic acid PCR amplification of secretions from a nasal swab or wash
The pediatric patient older than approximately 5 years of age with LRTI typically has ?
Mycoplasma
orgs listed for younger groups can occur as well
abx coverage for ped pneumonia pt 5+ yrs
(coverage for mycoplasma and S. pneumo)
penicillins (amoxicillin, ampicillin), cephalosporins (ceftriaxone, cefuroxime), or macrolides (azithromycin). Vancomycin or clindamycin if CAP MRSA is suspected
Pneumonia in the intubated intensive care patient with central lines may be related to ? or ?
Pseudomonas aeruginosa or fungal species (Candida)
? are possibilities in the patient with chronic lung disease (cystic fibrosis)
Pseudomonas and Aspergillus
5-mm induration may be considered a “positive PPD” at 48 to 72 hours in a patient with ?
confirmed exposure, abnormal CXR, or immunodeficiency.
Standard antituberculous therapy, while awaiting culture and sensitivities, includes ?. For possible drug-resistant organisms, ? can be added temporarily as long as visual acuity can be followed
isoniazid, rifampin, and pyrazinamide
ethambutol
typical antituberculosis therapy
initial phase of approximately 2 months’ duration on three or four medications, followed by a continuation phase of 4 to 7 months on isoniazid and rifampin
9 to 12 months is recommended for CNS or disseminated TB
new TB tests
Quantiferon Gold In-Tube (QFT-GIT) test and the T-SPOT.TB (T-Spot) test
(both are interferon gamma release assays (IGRA))
Marfan syndrome inheritance? gene involved?
autosomal dominant, fibrillin-1 gene
cystathionine synthase deficiency is seen in what condition
homocystinuria
OCD treatment
high-dose SSRI (i.e. fluoxetine) and exposure and response based therapy
fever, severe headaches, and focal neurological changes are the classic triad for
brain abscess
cyanotic congenital heart disease and recurrent sinusitis increases the risk for
brain abscess due to spread of bacteria from sinuses into frontal lobe and heard defect bypasses bad-filtering lungs (R->L shunt)
abdominal pain, hematemesis, metabolic acidosis, radiopaque lesions in stomach on Xray, think ingestion of ?
iron
scoliosis, “hammer toes”, HCM, dysarthria, frequent falling think?
Friedrich ataxia, most common type of apinocerebellar ataxia
autosomal recessiv
The degree of proteinuria significant enough to warrant further diagnostic workup is defined as:
30 mg/dL (1+) on 2 random urine specimens collected one week apart if urine specific gravity is < 1.015; or
100 mg/dL (2+) on similarly collected urine if specific gravity is > 1.015.
24 hr urine collection ranges for normal, abnormal, and nephrotic range
Normal: Amount of protein excreted is < 4 mg/m2/hour
Abnormal: 4-40 mg/m2/hour
Nephrotic range: > 40 mg/m2/hour
Urine Protein:Creatinine Ratio (urine PCR)
less than 0.2 is normal in children older than 2 years (less than 0.5 is normal in 6- to 24-month-olds)
greater than 1.0 is in a suspicious range for nephrotic syndrome
greater than 2.5 is diagnostic for nephrotic syndrome
other lab findings in nephrotic syndrom
hypoalbuminemia, hyperlipidemia, hyponatremia (fluid overload and hyperlipids)
general treatment of nephrotic syndrome
corticosteroids and sodium restriction to a level of 1500-2000 mg daily.
treatment of nephrotic syndrome if symptomatic (particularly to relieve dyspnea and edema if these symptoms are causing discomfort, or, in boys, to reduce scrotal edema that may compromise testicular perfusion)
25% albumin infusion followed with 1 to 2 mg/kg of furosemide to promote diuresis
infectious complications of nephrotic syndrome
spontaneous peritonitis (S. pneumo, G-) pneumonia, cellulitis, UTIs
