Category Archives: Clinical

Lumbar puncture

Traumatic tap

Increasing RBC counts were statistically associated with increasing WBC counts (P < .001). But in febrile babies under 90 days,where RBC < 10 000/mm3 no real impact and reference range for WBC in uninfected infants with traumatic lumbar punctures was still 0 to 16/mm3.

CSF protein increased linearly with increasing CSF RBCs (up 1.1 mg/dL for every 1000 RBC).

Correct 500:1?  Sounds good in theory, but not in practice.  Predicted leukocytes matched observed leukocytes poorly for 682 CSF specimens.  Adjusted blood counts in CSF have no advantage over uncorrected counts for predicting bacterial meningitis. [PIDJ 2006;25(1):8-11DOI: 10.1097/01.inf.0000195624.34981.36 · ]

 

Rheumatic fever

Rare in developed world now, still common in underdeveloped world, or at least in underdeveloped communities eg Aboriginal Australians.  Prob also genetic susceptibility.

Caused by Group A streptococcus.  Important cause of acquired heart valve disease.  Can recur.

Probably cross reactivity between specific Group A strep M proteins and human tissues.

Erythema marginatum
Erythema marginatum

Diagnosis

Jones criteria:

  • Major
    • Carditis eg new murmur.  Mitral most commonly, classically apical blowing pan-systolic.  Aortic next most common.
    • Arthritis esp large joints.  Migratory.
    • Subcutaneous nodules – these are the most uncommon major criterium (in Turkish study of over 1000 cases there were none with nodules).  Typically over extensor surfaces of joints, 0.5-2cm, symmetrical.
    • Sydenhams chorea
    • Erythema marginatum – not specific to rheumatic fever. Seen in 0.4% of Turkish study patients. Serpiginous or annual eruption, can look similar to erythema multiforme. Provoked by warmth eg bath.  Non pruritic.
  • Minor
    • Fever
    • Arthralgia
    • Prolonged PR interval on ECG
    • Elevated CRP/ESR
  • 2 major or 1 major plus 2 minor, plus confirmation of group A streptococcal infection eg positive culture, high ASO titre sufficient for diagnosis. Modified Jones takes into account background incidence.

Note that initial infection may be subclinical eg pharyngitis, erysipelas. Symptoms of rheumatic fever develop 10 days to several weeks later. Chorea can appear months later.  Low threshold for echo as carditis can also be subclinical.

Established criteria for rheumatic valvulitis – Gewitz 2015

Treatment

Antibiotics – Treat with penicillin,  this does not however affect clinical course but hopefully prevents further spread of that particular bug. Traditionally single dose intramuscular Penicillin G Benzathine.

NSAIDs for joint pain.  Usually dramatic response, if not then reconsider diagnosis!

Valproate for chorea, possibly steroids – see Sydenham’s.

Aspirin and/or Steroids for carditis, but not much evidence.  Diuretics, ACE inhibitors for cardiac failure.

Long term treatment

Recurrence with progression of valve damage is the main concern, and well recognized. Subclinical carditis improves in about 50% but definite risk of progression (mild definite and borderline RHD showed 26% and 9.8% echocardiographic progression respectively).

Regular intramuscular penicillin (benzathine pencillin G) every 2-3 weeks has the lowest recurrence rates but oral penicillin V more acceptable.  Erythromycin or cephalexin if allergic.

WHO recommendations:

  • Rheumatic fever without carditis: 5 years after last attack or until age 18 (whichever is longer)
  • Rheumatic fever with carditis but without residual disease: 10 years after last attack or until age 25 (whichever is longer)
  • Residual valve disease or valve replacement: lifelong

American and Australian heart association guidelines vary slightly:

Penicillin prophylaxis guidelines comparison

Seizures

Seizures, fits, funny turns, convulsions, attacks…  None of these really has a medical meaning.  Convulsion suggests rhythmic motor activity, but that’s about it.  The implication of most of these is that there is excessive abnormal, involuntary muscle contraction, usually bilateral.  But more broadly, some involuntary, usually sudden and self terminating episode of abnormal (or at least non-purposeful) activity and/or impaired awareness. Can be sustained or interrupted.

Nottingham RCPCH approved guideline distinguishes:

  • Febrile?
  • Already on anti-epileptic medication?  Consider checking levels, or at least storing sample.
  • Predisposing conditions? eg neurodevelopmental problem, brain injury/surgery.
  • Neonate or young infant? Some additional possibilities eg hypoxic ischaemic encephalopathy (HIE), Fifth day fits, drug withdrawal (neonatal abstinence syndrome), pyridoxine dependent epilepsy.

Most commonly Febrile convulsions ie age related, benign.  Beware complex (multiple seizures in same illness, focal features, prolonged >15 mins) and any abnormal findings eg neck stiffness, bulging fontanelle, prolonged illness, abnormal cognition before/after.

Important differentials are:

  • meningitis
  • encephalitis
  • shaken baby (non-accidental injury)
  • brain tumour/haemorrhage, hydrocephalus
  • ingestion (deliberate or accidental)
  • metabolic (low glucose, calcium/magnesium, low/high sodium)

May represent first evidence of epilepsy.

Horner’s syndrome

Horner’s syndrome = small pupil, ipsilateral ptosis +/- reduced sweating.  Compare Holmes Adie pupil.

Anhidrosis localizes lesion to preganglionic branch.

Turn down the lights to make it more obvious!  Look for associated Klumpke’s.

In babies usually congenital or related to birth trauma, rarely it can be due to:

Other cranial nerve involvement clearly points to brainstem problem.

[British Journal of Ophthalmology 1998;82:51-54. ]

Penis problems

The foreskin cannot, and should not, be retracted in newborn babies.  It should gradually begin to separate in the first few years of life.

Recurrent balanitis leads to scarring around the meatus, so that you cannot see the slit opening of the penis itself.  In this case, the foreskin will balloon on passing urine (a minor degree of this can still be seen in children without scarring.

Can try application of topical steroid creams: 0.05% betamethasone cream should be used twice daily for 2 to 4 weeks.  Gently retract foreskin without causing any discomfort and apply a thick layer of cream to the tightest part of the foreskin.  Steroid creams of higher potency may be tried if this fails.

Circumcision if significant phimosis and steroid creams fail.

Smegma pearls

Retained smegma can accumulate into substantial but painless lumps down the shaft of the penis.  Can be ignored.

Balanitis Xerotica Obliterans

A form of lichen sclerosus affecting the tip of the penis, causing white, crinkly thickening.

Trichotillomania

Or repetitive hair pulling.  Previously classified as an impulse control disorder, ie a sense of tension that is only “satisfied” when hair is pulled out. However, many children do not get this tension and gratification so in DSM-V trichotillomania is included among obsessive-compulsive and related disorders.

Dutch cohort mostly girls, literature says no gender difference!   Nail biting can co-exist, as can stereotypies.  Many kids will also eat their hair once it is pulled out.  Most common age of onset is in early adolescence (9-13 years), but frequently occurs in early childhood, even as early as 12 months of age.  Triggering factors identified include concerns about physical appearance, family and school issues, and concurrent illness.  Parents sometimes also pull their hair, so maybe (partly) learned.

Two distinct types of trichotillomania described: automatic and focused

  • Automatic – outside of own awareness, may not recall actual pulling, but may admit to ‘playing with their hair’ or may have been noted to pull their hair in a distracted state.  Children tend to fall into this category.
  • Focused – aware, in response to negative emotion or urges

Parents often miss the hair pulling and only present when hair clumps noticed on surfaces (esp bed –  presumably due to pulling in sleep) or bald patches appear.

On Examination

Exclamation mark hairs (thin proximally, at scalp, normal distally), usually thought of being evidence of alopecia areata, may be seen, so not very predictive.  Pull test – gentle traction on about 20 hairs in 3 different locations.  Positive if more than 5 hairs extracted – suggests active alopecia areata.  You may miss dormant alopecia, but in that case hair regrowth should occur.

[https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4857813/]

Stereotypy

Where children present with abnormal movements, consider:

Stereotypies are repetitive non-functional movements, typically hand flapping or twisting, body rocking, head banging/nodding, grimacing, arm flapping. As with tics, there is often a family history, and there is an association with obsessive compulsive tendencies.

They can be present in children with normal development, but are a feature of neurological disorders especially autism spectrum disorder and sensory impairment.  In these children, the movements are part of a period of introspective absorption, they make prefer such activity to conventional social interactions.

There are a number of differences from tics, although they can co-exist:

  • Sterotypy presents younger, eg under 2 yrs.  Tics present from 4 onwards.
  • Tics can vary over time, so grimacing moves on to  shoulder jerks, then moves on to clearing throat.  Stereotypy movements are unchanging.
  • Stereotypy movements are rhythmic, rather than just a single jerk
  • Tics are brief, stereotypy can be prolonged
  • Tics have a premonitory sensation (although only older children may be aware)
  • Tics can be suppressed with effort.  Children with stereotypy can be distracted but may resent it! (Similarly self gratification)

Excitement and stress are triggers for both.  Over time, the child usually becomes aware of social disapproval and may suppress the behaviour except in secret!

[Ulster Med J 2014;83(1):22-30]

 

 

 

Sacral dimple

Typical sacral dimples are <5mm in diameter, within 25mm of anus and located in midline.  Rate of spinal  dysraphism (bifida occulta) less than 1%.

Higher risk if do not fulfill these criteria. Lipomas, deviated/bifurcated crease are the most likely to be associated with dysraphism.  Otherwise you expect at least 2 or more cutaneous markers (hair tuft, haemangioma, Mongolian spot, skin tag/tail).

Reports of high frequency of hair tufts in diastematomyelia probably refer to more striking lesions (“faun tails”).

Royal College of Radiology has policy  – ignore sacral dimples unless atypical, or in combination with other lesions.

USS if neonate, but MRI if US abnormal or equivocal, where neurological signs (bladder, bowel, lower limb) or lesion discharging.

[Arch Derm 2004]

Episodic autonomic symptoms

  • Facial symptoms (eye/nose watering, flushing) can be related to cluster headache.
  • POTS (Postural orthostatic tachycardia syndrome) – more common in females.  Orthostatic tachycardia (NOT hypotension), dizziness, chest pain, palpitations, headaches, dyspnoea.  Sometimes bluish red discolouration in lower limbs.  No known cause, can have sudden onset in previously fit individuals.  Associated with Ehlers Danlos (venous return problem?).  Can be debilitating, associated with chronic pain, sleep problems, GI symptoms.  Can improve over time.  Diagnosis – heart rate increases by 30 beats per minute (bpm) or more (40bpm in those aged 12-19) after 10 minutes of standing, or if it increases to more than 120bpm. Consider treatment with beta blocker, fludrocortisone, SSRI.
  • Metabolic disorders (disorders of fatty acid oxidation, organic acids, urea cycle or glycosylation)
  • Acute hydronephrosis
  • Addison disease
  • Brain tumours and other masses in the head
  • Familial dysautonomia
  • Spinal dysreflexia
  • Phaeochromocytoma can cause headache and sweating, but anxiety and palpitations should be prominent, with hypertension (or at least orthostatic hypotension).
  • Carcinoid causes flushing
  • Occipital lobe epilepsy
  • Scombroid toxicity