Category Archives: Clinical

Chest X-ray

Interpretation

  • Start outside, work in – soft tissues, then bones, then lungs/heart, finally neck/infradiaphragmatic.
  • Safety check – position of lines/tunes, check apices for pneumothorax, any foreign bodies?

Adequacy

  • Rotation – look at symmetry of clavicles and anterior rib ends.
  • If clavicles high, then lordotic film. May obscure apices.
  • Penetration – should just be able to make out intravertebral spaces, without lung fields being too dark.
  • Inspiration – hila become artificially prominent if underinflated.

Thymus

Pesky thing! Can look like pneumonia. Latter more likely if air bronchograms, volume loss (displaced fissure/trachea/mediastinum), effusion. Classically:

  • indentations where ribs overlie.
  • Pointy outside edge (“sail sign”).
  • No mass effect
  • Lowish density – should still be able to see vascular markings of lung behind

Spinnaker sign is where pneumomediastinum around thymus creates long curving line.

Other normal things

Azygos lobe – normal variant where RUL has near vertical line extending up and out, giving impression of mediastinal mass.

Mach effect – a line parallel to heart border, looks like pneumocardium but actually optical illusion where your eye “detects” border where there isn’t one…

One diaphragm usually higher than other – both ok, as long as no more than 2cm (one rib space).

Other

Hilum – rings or tram lines suggest bronchitis. Round opacity adjacent to and larger than ring suggests vascular prominence due to left to right shunt.

Silhouette sign – where heart border and/or diaphragm obscured in lower zone due to consolidation in lower lobe (left or right).

Effusion – vertical line at costophrenic angle.

Round pneumonia – will have air bronchograms, compare mass.

Collapse vs consolidation – sharp lower border is the fissure so if deviated then collapse.

Pneumothorax – lucency without clear edge may suggest lung hyperinflation eg bronchial atresia.

If edge projects below diaphragm then likely to be skin fold!

Foreign body – get expiratory film, which will enhance air trapping.

Diarrhoea

According to NICE, 3 or more loose or liquid stools in a day (or more frequently than is normal for the individual) counts as diarrhoea.

Persisting for more than 14 days makes it chronic.

Acute typically gastroenteritis. Presence of blood and/or mucus suggests more invasive inflammation, viz colitis.

In kids, can occur with pretty much any illness!

Vomiting with diarrhoea makes a primary gut cause more likely, but still not specific.

Bloody Stools

Bloody stools, think VTEC rules!

Acute bloody diarrhoea usually infective –

  • Shigella/salmonella (non typhoid strains)
  • Campylobacter
  • E coli (some, eg EHEC)

Usually worse abdominal pain than usually seen in gastroenteritis, can also be high fever. If severe, shigella/campylobacter can be treated with antibiotics.

If chronic, consider

Some serious causes:

Murmurs

An added sound heard when listening with a stethoscope, distinct from heart sounds or other clicks or snaps.

Can indicate a structural abnormality.  But can be heard in normal hearts too, esp kids.

Still’s murmur

Or “innocent” murmur.  Characteristic vibratory, crescendo-decrescendo sound, loudest along left sternal border.  Never louder than grade 3.  Typically gets quieter when child stands up (you would not expect a murmur caused by a structural abnormality to change).

Venous hum

Another innocent one, a rumble heard in the upper chest, disappears when lying down, or when neck turned or neck veins occluded gently.

Pulmonary flow murmur

Pulmonary valve closest to anterior chest wall, which might explain why you sometimes hear this.  Might be confused with pulmonary stenosis or subaortic membrane.

Roseola

Or erythema subitum.  Dramatic viral rash.  Caused by Herpesvirus 6 and 7.

Classically high fever, URTI symptoms or no focus, potentially febrile convulsion!  Then rash appears as fever subsides, day 2-4.

Rash is widespread fine maculopapular, can be pale haloes around spots, mostly on trunk.  Can be in mouth!  Not itchy.

 

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.

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.  Typically over extensor surfaces of joints, 0.5-2cm, symmetrical.
    • Sydenhams chorea
    • Erythema marginatum – not specific to rheumatic fever.  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.

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.

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.  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 heart association guidelines vary slightly.

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 all of these is that there is excessive abnormal muscle contraction, usually bilateral.  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.

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:

  • cervical or mediastinal neuroblastoma (look for mass in neck or abdomen, heterochromia (eye changes colour!) or
  • carotid vascular lesion or
  • apical pulmonary abnormality.

Other cranial nerve involvement clearly points to brainstem problem.

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