UMEM Educational Pearls - Pediatrics

While breastfeeding is still the preferred source of infant nutrition by the AAP, a little-known fact is that breastfeeding may expose the nursing infant to environmental pollutants to which they might not normally be exposed.  If you have a mother that appears ill due to exposure to any of these agents, don't forget to have the infant examined as well for signs of intoxication.

• Breastmilk can contain approximately 20% of the maternal toxin load, which can produce more severe effects in the infant due to the vastly different dose/weight ratio
• Toxin load is usually due to the lipid solubility of agents
• Formulas are safe due to the nature of their fat sources;  cows usually have a much lower exposure rate to pollutants, and those that are ingested are much more dilute due to the volume of milk produced in comparison to a human female;  also, with non-cows'-milk formulas, the lipid components are usually plant-derived and thus also with a lower risk of exposure
• Common offending agents include:  DDT, PCBs, Dioxin, hexachlorobenzene, Halothane, carbon disulfide, nicotine, lead, methylmercury, Heptachlor, Chlordane, and tetrachloroethylene

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• although newborn screening for PKU has been routine throughout North America since the 1960's, it is not routine in undeveloped countries (beware immigrants, foreign visitors)
• PKU is caused by phenylalanine hydroxylase (PAH) deficiency which catalyzes the conversion of phenylalanine to tyrosine
• neonates with PKU typically show no physical signs of hyperphenylalaninemia
• children with untreated PKU have impaired brain development with poor brain growth, seizures, behavior problems, and severe mental retardation
• affected individuals exude a pungent, musty odor due to elevated phenylalanine levels which also causes skin conditions such as eczema
• because there is absent tyrosine production with reduced tyrosinase, the hair and skin are very lightly pigmented
• early diagnosis and management with a low-phenylalanine diet eliminates these complications; and once treated, affected children are healthy and do not require hosopitalizations

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• Although rare, it is a serious life threatening entity of pediatric emergency medicine
• Must be in the differential of those with signs of increased intracranial pressure or focal deficit and hx of sinusitis, mastoiditis or cyanotic congenital heart disease.
• Investigation and diagnosis primarily with CT scan
• CSF studies demonstrate sterile fluid with elevated protein, and mildly elevated WBC
• Antibiotic coverage should be broad Naficillin/Vanc + Ceftriaxone + Metronidazole, until speciation and susceptibilities obtained from surgical specimen
• Steroids reserved only in cases of imminent herniation
• Controversy exists over prophylactic anticonvulsants
• Mortality recently <10% attributed to early diagnosis and appropriate antibiotic coverage.

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You've probably long been taught that Sickle Cell Trait is an irrelevant piece of the PMH, unless you are a genetic counselor.  Well, thanks to Dr. Rolnick and a literature search, I (and now you) know that that is incorrect.

Though Sickle Cell Trait (SCT) does not cause exactly the same pathologies as Sickle Cell Disease (SCD), there are believed to be a variety of RBC abnormalities associated with HgbS (such as measurably lower RBC deformability, and low levels of sickling under extreme heat and exercise conditions) which contribute to increased exercise-related sudden death.  In one NEJM study of all deaths among 2 million (MILLION) military recruits over a 4 year period, the relative risk of otherwise unexplained sudden death for black recruits with HgbAS vs. black recruits without HgbS was 27.6 (p<0.001), and 39.8 (p<0.001) for all recruits (HgbAS vs. no HgbS).

I must say that this topic is not controversy-free, however, I should also note that my search for "Sickle Cell Trait and Sudden Death" turned up quite a few articles directed at plaintiff's attorneys. 

The take-home point is that SCT is likely not a benign condition, and you must be cautious in telling patients that it is.  Again, this phenomenon is best described in patients undergoing extreme physical exertion, but hopefully this will change how you think about SCT.

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Infantile Spasms (West Syndrome):

• Are brief contractions of the neck, trunk, arm, and leg muscles that last 2-10 seconds
• Are NOT seizures, but 86% of children with infantile spasms go on to develop a seizure disorder before 1 year of age
• Usually occur as the child is going to sleep or waking up
• Most commonly seen between 3 and 8 months of age
• Often mistakenly diagnosed as colic
• Poor prognosis as infantile spasms usually indicate an underlying genetic, metabolic, or developmental abnormality

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• Status epilepticus is defined as either a continuous convulsion or serial convulsions without loss of consciousness that lasts 30 minutes.
• First line treatment:  benzodiazepine because it is absorbed rapidly into the nervous system; lorazepam (0.05 to 0.1 mg/kg) is preferred over diazepam (0.2 to 0.5 mg/kg) because of its longer half-life in the CNS; rectal administration of the intravenous formulation or the commercially available gel at the same doses may be subsitutued if no IV is attainable.
• if seizure activity persists beyond 10 - 15 min, a longer acting anticonvulsant such as phenytoin (18 -20 mg/kg), fosphenytoin, or phenobarbital (18 - 20 mg/kg) is administered; they take longer to penetrate the CNS, but have much longer half-lives than the benzodiazepines.  Phenobarbital is given to infants while phenytoin or fosphenytoin is given to older children.
• Fosphenytoin, a prodrug to phenytoin, increasingly is replacing phenytoin as the drug of choice.  It can be administered at two to three times the rate of phenytoin and is less caustic to skin in teh event of vein extravasation.  It can als be given intramuscularly, while phenytoin can't.

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Hypertensive encephalopathy is generally seen in children with renal disease, e.g. acute glomerulonephritis or ESRD. 

Signs and symptoms include bp >99th percentile for age and height and neurologic impairment.  May present acutely with seizure or coma, or subacute with HA, vomiting, lethargy, blurry vision or change in mental status.  Exam findings may also include papilledema.

MRI may show increased signal in occipital lobes of T2 weighted images, known as reversible posterior leukoencephalopathy.

Treatment is to lower BP by 20-25% for the first 8 hours and to normative levels over 24-48 hrs.  IV therapy with esmolol drip, labetalol or nicardapine are the treatments of choice.  Nitroprusside prudent in most hypertensive adult emergencies must be used cautiously  if history of renal disease secondary to cyanide toxicity. Seizure should also be treated as you would with status epilepticus.

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PEARL: Any patient that in your Emergency Department with a sickle cell disease (SCD)-related diagnosis requires incentive spirometry and frequent monitoring for acute chest syndrome (ACS).

BRIEF WHY: ACS is the most common cause of hospitalization and death in patients with SCD.^1,2 

Nearly half of all patients who develop ACS are admitted for diagnoses other than ACS.  Of those not admitted with ACS, radiographic and clinical findings of ACS appeared a mean of 2.5 days after admission.² It is because of this that all patients with SCD related diagnoses at presentation, must be treated as though they are in the prodrome stage of ACS, and all require incentive spirometry to reduce the risk of progression to ACS.²

More to come... 

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Pertussis (Whooping Cough):

• Caused by B.pertussis and B.parapertussis
• Incubation period = 6 days
• Three stages:  Catarrhal (low-grade fever, rhinorrhea);  Paroxysmal (classic "whooping" cough);  Convalescent (resolution of symptoms over a ~2wk period)
• Full course of the disease = on average 6-8 weeks, although convalescent stage may last MONTHS
• Erythromycin may be effective early on, but no effect once in the paroxysmal stage
• Complications are most common in neonates and infants, and notably, the elderly
• Complications include apnea, hypoxia, pneumonia, encephalopathy, pneumothorax/pneumomediastinum (from paroxysms in the setting of severe mucus plugging)

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• peak age of coin ingestion is 1-3 years, 60% being males
• CXR is recommended, and if in esophagus the flat surface of coin is seen on the AP view with the edge seen on the lateral view
• if in the stomach, expectant observation (3-4 days) in the absence of abdominal pain and vomiting
• 20% of coins will lodge in the esoophagus at the level of the cricopharyngeus muscle, aortic arch, and lower esophageal sphincter
• the change in composition of pennies from cooper to zinc in recent years has increased the potential for mucosal corrosion
• all coins lodged in the proximal esophagus should be removed endoscoopically as soon as possible
• coins in the mid- to lower esophagus may be observed for 12-24 hours if asymptomatic, but should undergo endoscopy if the coin fails to pass in that time period

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• triad of chronic sinusitis, bronchiecctasis, and situs inversus
• recurrent acute otitis media and nasl polyps also common
• syndrome is due to an ultrastructural abnormality of the cilia in which dynein arms are absent resulting in ciliary dysfunction and mucus stasis and frequent sinopulmonary infections
• situs inversus is due to the absence of the influence of cilia function on viscera development
• diagnosed by bronchoscopy for cilia biopsy

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• results from failure of the upper femoral epiphysis, which allows displacement of the femoral head on the femoral neck
• onset may be sudden, but more often is gradual
• pain frequently is referred to the knee, but can also occur in the hip
• limp and out-toeing are common, with loss of medial hip rotation
• majority of patients are 7-15 years old, and are aboce the 95th percentile for weight
• AP or frog-leg lateral xrays of the hip are diagnostic

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• CNSD, also known as toddler's diarrhea
• the most common cause of chronic diarrhea in childhood
• possibly a variant of irritable bowel syndrome, family history of IBS is common
• children are 6-58 months of age, most commonly 11-24 months old)
• otherwise in good health with normal weight gain, without signs of malabsorption syndrome or enteric infection
• morning stool is the most formed, with the stools becoming progressively looser through the day that are malodorous with food particles
• most often due to dietary factors causing altered gastrointestinal motility such as reduced fat intake or excessive fluid intake, especially sucrose-containing fruit juices
• treatment is based on modification of the contributing dietary factors

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Noninvasive ventilation use in children has been shown in some trials to be a useful tool to avoid intubation in children with asthma.

Since children with asthma who are intubated have a much higher risk for complications including pneumotharaces and pneumomediastinum this can be a very useful tool.

Bi-Pap is usually started with typical settings of 10 for IPAP and 5 for EPAP and can be titrated up as tolerated to levels of up to 25/20 cm H2O and can be delivered with a set rate or a back up rate.

Albuterol and nebulized epiephrine may be delivered through newer BiPAP machines.  

Signs that BiPAP is working include decreased Respiratory Rate, decreased retractions and accesory muscle use, improved oxygenation saturation

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• Characterized by proteinuria, hypoalbuminemia, edema, and hypercholesterolemia
• Abnormal Vitals:  tachypnea (due to pulmlonary edema); tachycardia (intravascular depletion); hypertension
• Abnormal PE:  peripheral edema, ascites, S3 on ausculation
• UA demonstrates significant proteinuria.
• TX is uniformly with oral steroids.

• Rates are highest for children <5yrs and between 15-24 yrs old.
• Most of pathology is related to duration of asphyxia from time of submersion until adequate respiration is restored.
• The brain and heart are most vulnerable to anoxic and ischemic injury.
• Prognosis for near-drowning depends primarily on the degree of brain anoxia.
• Prolonged submersion (>25 min); apnea or coma at presentation to ED; and initial arterial pH <7.0 are all poor prognostic indicators.
• 96% of victims who require <10min of CPR survive with no or only mild neurologic impariment.

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Classic presentation:  breastfeeding failure with umbilical stump and gastrointestinal bleeding by postnatal day 7.  Oozing from circumcision, venipuncture, and heel sticks is also common.  Beware bleeding into the scalp or intracranial space.

Due to essential vitamin K deficiency which exists at birth as the fetus receives little vitamin K from the uteroplacental circulation.  It is responsible for impaired neonatal clotting function (deficiency of factors II, VII, IX, and X).

Prevented by a single intramuscular dose of 1mg vitamin K in the first few hours following delivery.

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Pancytopenia manifests as a decrease in the erythroid, myeloid, and megakaryocytic cell lines that appears as a decrease in red blood cells, white blood cells, and platelents on complete blood count analysis. 

• Indicates bone marrow failure
• May be due to invasion of marrow by nonneoplastic (such as drugs, chemicals, irradiation, or infections) or neoplastic conditions
• Clinically manifests as pallor, easy fatigability, and weakness due to anemia; purpura, epistaxis, and bruising due to thrombocytopenia; and increased susceptibility to infection due to leukoopenia.

Pancytopenia is an absolute indication for bone marrow aspiration and biopsy to delineate and treat the cause.

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• Increasing use of OTC meds is a worldwide occurence with $3.5 billion each year spent in the US.
• About 4 million children younger than 12 yrs are treated with these meds each week in the US.
• In 2007 the FDA recommended that the use of OTC cold meds (antihistamines-brompheniramine, chlorpheniramine, diphenhydramine, doxylamine; antitussive-dextromethorphan; expectorant-guaifenesin; and decongestants-pseudoephedrine and phenylephrine) be prohibited in children < 6 yrs.
• A recent review of 103 childhood deaths due to OTC meds found that most deaths were from product misuse rather than adverse effects resulting from recommended doses particularly when the product was used with the intent to sedate a child. 
• Children less than 2 years old were most susceptible to death using these products which is why manufacturers voluntarily withdrew the use of OTC meds in this age group.

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• Scabiess requires sensitization to the organism, Sarcoptes scabiei. 
• It may take weeks before pruritus develps in a child infested for the first time.  On the next exposure, however, INTENSE itching will occur within 24 hours. 
• Burrows in the webs of fingers and toes are common.
• Treatment:  Firstline is permethrin 5% cream on the entire body from the neck down, and wash off after 12 hours.  Alternative is lindane 1% (1oz of lotion or 30g of cream) applied in a thin layer over the entire body from the neck down, and thoroughly washed off after 8 hours OR ivermectin 200ug/kg orally repeated in 2 weeks.
• Many avoid lindane because of neurotoxicity.  Do not apply it after a bath, or to someone with extensive atopic dermatitis as seizures have been reported.
• Decontaminate all bedding and cloting.
• Warn patients that the rash and itching may persist for up to 2 weeks after treatment.

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