Tag Archives: peds

septic arthritis vs. transient synovitis in kids

3 Nov

repost of an old entry, but came up again recently, worth a review:

–lots of overlap in signs/symptoms
–one article came up with a decent decision rule

J Bone Joint Surg Am. 1999 Dec;81(12):1662-70.
–looked at 282 cases, excluded 114 atypical patients (e.g. immunocompromised), leaving 168
–38 had “true” septic arthritis
septic arthritis defined by positive culture or joint WBC >= 50,000 cells/mm3

–four things they decided on that might differentiate:

  • history of fever
  • non-weight-bearing
  • erythrocyte sedimentation rate (ESR) >= 40 mm/hr
  • serum WBC > 12,000 cells/mm3

–predicted probability of septic arthritis using these four predictors:

  • < 0.2 percent for zero predictors
  • 3.0 percent for one predictor
  • 40.0 percent for two predictors
  • 93.1 percent for three predictors
  • 99.6 percent for four predictors

–septic arthritis is bad, transient synovitis not so bad
–hard to tell sometimes, signs/symptoms are often similar
–useful: history of fever, non-weight bearing, ESR>40, WBC>12k
–if none of the above: unlikely septic arthritis
–more of the above: worry a bit more

Reference(s): kocher article, picture


pertussis: quick hits

17 Feb

(Should’ve been posted earlier, but didn’t make it up somehow.  Here it is now, though, for your learning pleasure).

Pertussis is bad and increasing – it kills ~300,000/yr in non-vaccinated places & can cause serious systemic issues like vert dissection, etc.

– B. pertussis starts like a viral URI (cough, rhinorrhea, malaise)

incubation period is about a week or so, and it is very contagious by air particles (use precautions!)

– more common in older adults who have waning immunity.

– The danger is for passing it to infants who have not immunity.

– In older adults, it is persistent cough lasting ~3-4 weeks and getting worse from week 1 to 2. Often paroxysmal.

– In infants, it is flu-like symptoms followed by paroxysmal cough with whooping inspiration against a closed glottis.

– Protect against pertussis with DTaP or Tdap.

– Test for pertussis with PCR (earlier) or culture (later)

– Treat pertussis early if possible, use Azithromycin

– Treat in those with high suspicion, those exposed, and those with suspicion with infants at home.


Submitted by J. Stone.


Sources: uptodate.com;  EMRap podcast discussion; picture

PECARN themes

13 Nov

Why don’t we just CT everybody?

  • estimated risk of lethal malignancy from a head CT
    • 1 year old -> 1 in 1000-1500
    • 10 year old -> 1 in 5000
  • clinically-important traumatic brain injuries in children was RARE
    • 0.9% had a clinically-important traumatic brain injury
    • 0.1% underwent surgery
    • study of over 42,000 children


Check out MDCalc’s handy tool for using the PECARN rule, but some common themes prevail:

  • GCS =14 (PECARN study included those with GCS 14-15, but GCS <14 would not be particularly reassuring)
  • signs of basilar skull fx (or palpable fx if < 2yo)
  • altered mental status (e.g. Agitation, somnolence, repetitive questioning, or slow response)
  • if <2 yo, scalp hematoma
  • LOC
  • vomiting
  • severe headache
  • severe mechanism of injury


risk of clinically important TBI, if you had:

  • none of the above: risk is <0.05 %
  • any of the RED clues: risk is 4+ %, probably should CT
  • no RED, but any of the other clues: risk 0.9%, consider obs vs CT


References: MDCalc; picture


Maple Syrup Urine Disease: clear the cobwebs

19 Sep

Maple syrup urine disease (MSUD)

an autosomal recessive metabolic disorder due to deficiency of the mitochondrial branched-chain alpha-keto acid dehydrogenase (BCKD)


Say what??? 


The body is unable to break down certain branched chain amino acids (BCAA) causing elevated blood levels of BCKD and increased urinary excretion of  BCAA -> sweet smelling urine



Typically diagnosed on newborn screening, however initial presentation in a newborn would be irritability, poor feeding, vomiting, lethargy, and ketonuria within 48 hours of birth.

Eventually leading to neurologic manifestations of dystonia, seizures, and cerebral edema.



So, I work in the emergency department… why do I care?


Episodes of acute exacerbation can occur in children who are usually controlled by nutritional management


Induced by intercurrent illness, exercise, injury, surgery, or fasting



Clinical manifestations of epigastric pain, vomiting, anorexia, muscle fatigue


Neurologic signs of hyperactivity, sleep disturbance, stupor, decreased cognitive function, dystonia, ataxia (in a child think about loss of previously mastered motor and speech function)


When in doubt, look for the acute onset of sweet smelling urine and send for qualitative urine organic acids to confirm



Aggressive treatment involves lowering concentrations of plasma branched chain amino acids (inhibiting protein catabolism and enhancing protein synthesis)

IV fluid resuscitation

treating the inciting cause (for example gastroenteritis, upper respiratory infection, etc.)

-hospital admission for serial neurological exams and monitoring for clearance of amino acids from the urine



K Estes


Source: Kleopa, K. A., Raizen, D. M., Friedrich, C. A., Brown, M. J. and Bird, S. J. (2001), Acute axonal neuropathy in maple syrup urine disease. Muscle Nerve, 24: 284–287.; picture

pediatric weight reference, in a pinch

17 Jun

handy chart from HMC web site:growth

Body Wt quick reference:

  • 2 mo old – 5 kg
  • 1 yr old – 10kg
  • 3 yr old – 15 kg
  • 5 yr old – 20 kg

Of course, every patient weight is variable, especially with obesity, but in tight spot (e.g. a code), you won’t be off by an order of magnitude.


Submitted by J. Rothstein.


References:  HMC site, CDC growth charts & picture

Neonatal sepsis (quick hits)

5 Jun

Difficult to r/o sepsis in kids under 3 mths. Higher risk in under 1 mth with fever > 38.0.

Sepsis workup includes:

  • LP,
  • blood and urine cultures,
  • CBC, CMP,
  • CXR.


Rochester criteria attempted to identify lower risk under 60 days includes:

generally well-appearing

previously healthy

o full term (at ≥37 weeks gestation)

o no antibiotics perinatally

o no unexplained hyperbilirubinemia that required treatment

o no antibiotics since discharge

o no hospitalizations

o no chronic illness

o discharged at the same time or before the mother

no evidence of skin, soft tissue, bone, joint, or ear infection

WBC count 5,000-15,000/mm3

• absolute band count ≤ 1,500/mm3

urine WBC count ≤ 10 per high power field (hpf)

stool WBC count ≤ 5 per high power field (hpf) only in infants with diarrhea


Treatment to cover for meningitis in neonates concern for sepsis:

Amp/gent/cefotaxime for under 1 mth.

May do vanc/ceftriaxone after 1 mth as no need to cover for listeria. Vanc to cover for beta lactam resistant strep/staph.


Submitted by J. Rothstein.


References: http://cid.oxfordjournals.org/content/39/9/1267.full.pdf+html; picture

Hemolytic Uremic Syndrome

25 Apr


-One of the most common causes for acute renal failure in children

-Mean age of presentation is between 3-5 years of age


Associated infections:

E. Coli 0157:H7 is the most common

-Shigella, S. pneumonia, and certain drugs are also associated with causing HUS


Concept of the Disease

-Fibrin strands form along blood vessels causing microangiopathic hemolytic anemia

-Renal dysfunction occurs directly from injury to the renal vasculature, as well as from platelet/complement deposit in the glomerular lumen.



-Prodromic gastroenteritis:  Abdominal pain, bloody diarrhea

-Later effects:  Thrombocytopenia, microangiopathic hemolytic anemia, renal failure



-Up to 25% of patients had long term renal injury

-Up to 12% of patients develop end stage renal disease or even death

-Recurrences are a possibility with a high mortality (up to 30%)



Gentle fluid resuscitation and supportive care

-Treatment of hyperkalemia when present

Transfusions as needed (platelet transfusions are reserved only in cases of bleeding)

-Antibiotics are not recommended for the gastroenteritis as they have been associated with increased release of verotoxin possibly increasing the risk for HUS

Plasmapharesis can be considered in severe cases


Submitted by Joey Grover. 


References: Rosen’s Emergency Medicine:  7th Edition.  picture