Saturday, 13 January 2007

Wallenberg Syndrome

This is an anonymised case of Wallenberg (Lateral Medullary) Syndrome, passed to me from another institution, in an elderly male patient whom had otherwise been of good health.

He had complained of sudden onset vertigo and nausea with vomiting. He described being unable to stand properly and he fell towards the right side. He also described double vision. He did not describe any subjective sensory abnormality or any limb weakness.

He had no previous medical history and took no regular medications.

He is a non-smoker and drinks occasional alcohol.

On examination, he was afebrile and looked well, pulse was regular and good volume, respiratory rate was 14 per minute and oxygen sats were 96% on room air.

His PNS examination was remarkable.

Tone was normal but he had a Left Pronator drift (consistent with an upper motor neurone defect). Power was 5/5 in the upper and lower Right limbs, but 4+/5 in the left upper and lower limbs albeit that his left side is the Non-Dominant side.

He was generally areflexic throughout.

However, the modality that had been alluded to was SENSORY testing and this revealed decreased sensation to light touch and painful stimuli (nociception) on the Left side.

His Right Plantar response was normal and the Left was Unresponsive.

Examination of his CNS revealed a Right sided Ptosis. Decreased sensation to both light touch and nociception of the RIGHT side of his face. His swallow reflex was normal.

Cerebellar examination revealed
rotatory nystagmus on the Right side and some mild horizontal nystagmus to the left. The patient had past-pointing on the Right side and dysdiadochokinesis was negative.

In summary, the Clinical Findings showed:

1) Dissociated sensory deficit (loss of sensation on the right face and left body)

2) Positive Cerebellar signs suggestive of a Right Sided Cerebellar Insult

3) Horner's Syndrome on the Right

4) Areflexia

5) Mild left sided weakness (although, this may be a natural difference due to it being the non-dominant side)

6) Vestibular dysfunction (symptoms of vertigo/nystagmus)

These above symptoms and clinical signs were consistent with a diagnosis of Wallenberg Syndrome (this diagnosis had also been confirmed by a very astute neurologist) a somewhat rare diagnosis, and this case will forever be in my mind as a typical case.

His CT scan showed a small infarct in his lower medulla and the MRA was non-diagnostic, nor was the diffusion MRI.

It reinforces for me that history and physical are a superb way to find out the problem, and putting all the pieces of the jigsaw together one can form the diagnosis where a scan may be unhelpful or at least difficult to interpret. Physical examination can show the physician where the problem is likely to be, and even if the scan is negative, the physical signs cannot be ignored nor should they be, as they will tell the doctor that the problem is present. Repeated physical examination will also tell the doctor whether the patient is getting better or worse!!

This patient was commenced on anti-platelet therapy and underwent rehabilitation.

A really great case!!

Friday, 12 January 2007

An Interesting Case

Yesterday was very interesting for me and it reinforced to me how important history taking really is. This next case has been anonymised for confidentiality purposes.

At another hospital, I hosted a conference, and a junior resident presented a history of a 45 year old female who presented to hospital with a seizure before New Year.

The patient had developed a fever four days before admission and apparently had no other symptoms until the day of admission, at which point, the patient had a seizure in her home toilet.

The patient had complained of some apparent neck stiffness on the day of the fever but not on admission.
The patient had no other medical ailments and took no regular medications. The patient is married, works as an airline hostess, smokes a box of cigarettes per day and consumes occasional alcohol in moderation.

At this point I stopped the Resident and asked for more history of the chief complaint before moving on with the previous medical history, but no more history was available, such as, had the patient had a recent cold, cough, sputum (and colour), any recent antibiotic therapy etc...

From here I heard the vitals which indicated a high temperature of 40 degrees C, SpO2 of 92%. Oxygen sats were too low for such a young patient.
At this point, it was possible to form differential diagnoses including the following:

Seizure and Fever: possible meningitis, encephalitis, cerebral asbcess, cerebral vasculitis, cerebral tumour / metastatic disease as examples.

Hypoxaemia and Fever: pneumonia, other respiratory infections, aspiration pneumonitis post-seizure, pulmonary embolism.

Bloods showed a high CRP>10 and raised white cell count of 18, although having a raised white count is not uncommon following a seizure.
Blood gas revealed a metabolic acidosis and hypoxaemia; urine analysis showed no sugar and 1+ ketones. Blood sugar was slightly raised at 187 but not diagnostic of DM on a random sample.

CT scan had revealed no abnormality, but lumbar puncture showed CSF pressure of 53cm water (normal <20),>

Hence, the diagnosis was confirmed to be meningitis, likely bacterial, from the CSF result, and I suggested from very little information and data at that time, that the patient had either a pneumonia causing meningitis, likely pneumococcal, or that the patient aspirated post-seizure.

I was then informed that the urinary pneumococcal antigen was POSITIVE. However, this does not itself rule out the possibility of a different organism having caused the meningitis, although it would seem highly likely that it was.

I considered that the acidosis and ketonuria could have been due to starvation or alcohol, but diabetic ketoacidosis was unlikely, as there was no sugar to be found in the urine and the serum glucose was not in the diabetic range.

Following this, we went to review the patient, and she had developed some retrograde amnesia from the illness and her husband was able provide an excellent history. She had developed a cough and green sputum before admission, and had seen her local doctor and a common cold had been diagnosed and antibiotics had probably been prescribed. The patient had only taken a few tablets, but she did not like to take medication and stopped it. The patient then drank alcohol following which she developed a seizure.

Examination yesterday was entirely normal in every respect except for a mild drug rash from antibiotics and some mild clubbing of her hands and feet.

The chest roentogen revealed some mild patchy alveolar change consistent with infection and the follow-on CT confirmed it was a pneumonia.

The acidosis was probably due to alcoholic ketoacidosis and / or starvation.
The fact that the patient had taken antibiotics prior to presentation explains the inability to find the bacteria in the CSF, but only thorough history taking was able to elucidate this information.

Thus, the chief complaint and in this case, limited history and simple vital sign recording even without knowing the full examination allowed us to formulate a differential diagnosis based on:

1) Knowledge of common causes of fever and seizures

2) Common causes of fever and hypoxaemia

3) Causes of metabolic acidosis and ketones with absent urinary glucose

In such cases, taking a thorough detailed history from a relative can save on time, allow a better idea of what is going on, and they can fill in the gaps that this patient could not possibly know due to her amnesia!

The simplistic way is to formulate a differential set of diagnoses, then ask the pertinent diagnostic questions to aim to prove or disprove the idea. If elements do not fit, then ask questions to try and find out why they don't fit and keep asking questions until you are satisfied.

Remember, a CT scan cannot ask a history!

Effective communication provides for effective history, which provides effective understanding and hence, treatment and understanding of patient presentations in hospital improves.

Basically, keep asking WHY and never be satisfied until you have the answers !

Finally, this patient has clubbing which suggests that she may have an existing underlying problem. However, clubbing is beyond the scope of today's long article, but I will endeavour to cover it in the future.

Wednesday, 10 January 2007

Drug History, Side Effects and Interactions

Taking a comprehensive drug history can be very important in establishing a diagnosis.

Nearly all drugs have side effects and interactions with other drugs, which sometimes makes their use problematic and confusing.

In the UK, generic named drugs are used when the patient is admitted into hospital even if they take a Brand Named drug because the vast majority of doctors will immediately be able to identify the class of drug, its mode of action and the dose range.

Writing Brand Names on a drug chart is discouraged as some hospitals will not stock that Brand of drug with them only having the cheaper generic drug available.

It is always important to check that the doses are correct because it may have been previously prescribed wrongly. Simply continuing a drug because another doctor wrote it up is clearly incorrect without first considering if the patient needed it in the first place or whether they still continue to need it or whether there are better drugs available (with less side effects and better efficiacy) to take its place.

I know of some doctors who have seen patients admitted into hospital taking three or four different benzodiazepine drugs and two or three anti-psychotic drugs and they have had the associated side effects as a result. Why? Well perhaps, the drugs were not checked and new ones added in. Sometimes, the patient does not even know what they are taking and when they get home from hospital, they continue taking the previous drugs from another clinic plus the newly prescribed ones, which if not careful, leads to polypharmacy and potentials for side effects and toxicity.

The UK has a GP system where a patient is assigned a local General Practitioner. When the patient has an ailment, they go to see their GP. They do not have any choice of other facility although they may wish to see one of the several doctors working in such GP practises.

All the drugs are updated on computer and there is an automatic warning of side-effects and drug interactions alerting the GP in case of an error.

If a patient is admitted to hospital and the drugs are not known, then a quick call to the GP practise and hey presto, the drugs are available to the hospital doctor-- unless it is 2am!!

In Japan, there is perhaps too much choice with patients flitting from one hospital to another getting second, third or fourth opinions, with drugs being prescribed here and there, perhaps without knowledge of the patient visiting other institutions making such prescribing somewhat concerning.

Even if the patient is admitted, it can be impossible to find out where the patient has previously visited or to obtain proper information. There is no apparent interlinking between local clinics and hospitals to aide the patient care.

Hence, coming back to the point, it is evermore important to take a detailed and comprehensive drug history.

Checking drug levels such as digoxin, phenytoin etc may provide important clues.

For example, I recently saw a 75 year old male who was 'off legs' and falling over with double vision. He was taking phenytoin for seizures secondary to a previous cerebral infarction (stroke). Examination revealed cerebellar signs including horizontal sustained nystagmus and positive dysdiadochokinesis plus generalised absence of reflexes-- all consistent with chronic phenytoin toxicity.

I hope that by reading this blog, residents will give the drug history more emphasis and give consideration that the drugs may in fact, be causing the problem rather than some weird and wonderful obscure syndrome. Remember, common things are common and when you hear hooves it is usually horses rather than zebras!

If you would like further information / advice then please leave a message.

Tuesday, 9 January 2007

The Hidden Pneumonia

The following case has been anonymised to safe guard patient confidentiality which is the prime importance of all doctors for their patients. However, there are important points to be drawn from the following scenario, which is as follows:

A very elderly man was admitted to another hospital with a chief complaint of fever, breathing difficulty and reduced conscious level-- it was sad because he was so ill.

He had suffered from a right sided stroke last year and was nursed flat and fed by nasogastric tube at home.

He was unable to give the resident any history, so as is commonly the case, the family or carers are the only ones to give a history if any at all.

In this case, the family mentioned that the patient had developed 'breathing difficulty' and his conscious level had decreased.

On admission, the patient was febrile (40 degrees C), shocked with a low blood pressure, tachycardia and his consciousness was decreased. His skin was very dry, JVP was not raised. Heart sounds were normal. His oxygen sats were 96% on nasal cannula oxygen, respiratory rate 24/min. Auscaultation revealed some fine right sided crackles, but left sided examination revealed course 'wet' crackles at the base and mid zone.

ABG revealed a compensated respiratory alkalosis and hypoxaemia on room air.

Clinically, this patient had a left sided pneumonia and dehydration.

Bloods revealed severe dehydration (Na 165, BUN 70, Creat 0.67), a normal white cell count but a high CRP >13. Urine analysis showed 3+ bacteria.

Such severe dehydration can occur due to the sweating phase component of fever, raised metabolic rate from infection, and also NG feeds can add to the problem as they contain standardised solutes which do not take into account the changes in body requirements, as in this case when water replenishment would have been of better advantage.

The junior resident rightly considered a urinary tract infection as a cause of infection and therapy was commenced for that. However, on first inspection, the Chest Roentogen (CXR) looks relatively normal for an elderly patient-- until you take a second look.

However, there was consolidation
BEHIND the heart shadow-- a hidden pneumonia. In any case, the history from his family and his physical examination provided the salient diagnostic clues. The Chest Roetogen is not there to make the diagnosis, it is taken to aide in the formation of a diagnosis.

If at first you do not see, look again, and stand back from the Xray. Unfortunately, on the above picture, the streaky consolidation which is evident on the CXR has not shown up particularly well.

When inspecting a CXR always look in areas that your eye would normally ignore, such as behind the heart, below the diaphragms, as pneumonias can be lurking in those places. Things that are usually missed on Xray are inspection of the ribs (looking for fractures / destruction from cancer), the clavicles, shoulder joints and scapulae-- all important structures. Moreover, the thoracic spine is also very important on a chest Xray, which is usually missed as well.

Don't just look at the lungs and the heart borders-- that is not inspecting an Xray in detail-- it is just the beginning. Also, don't forget to check the patient name!!

One final note of warning, patients being fed with an NG tube in a recumbent position may be predisposed to aspiration of their feed and hence, these 'at risk' patients should be nursed at an incline such that gravity will not allow for feed to regurgitate up the oesophagus and cause aspiration-- of course, never say never, it can still occur despite these measures.

Instructing the nursing staff to nurse these patients at an incline is a MUST and not to lie them flat and this also goes for patients with Cardiac failure and Respiratory Disease, in which patients, can become easily short of breath....but that is for another blog entirely, and I shall touch upon this area again in the future.

Monday, 8 January 2007


Since being in Japan on this occasion, I have seen at least 4 cases of endocarditis and heard of at least one other.

One case I picked up myself in my first week, and the only complaint was a fever in a very well looking patient sitting in his bed in front of me. The look of his poor dentition and a loud systolic murmur led me to the diagnosis, whereas the 'full body CT' performed on admission, had failed to elucidate the cause. Goal directed testing e.g. echocardiography picked up the vegetation and the patient received valve-saving reconstruction surgery.

More recently, two young female patients developed IE and one was found to have a 'floppy mitral valve' with regurgitation and blood cultures growing streptococcus salivarius (alpha-haemolytic strep) with the only contributing cause being dental work performed several months before; a classical case of subacute bacterial endocarditis. But for the experience and expertise of my colleague in the outpatient clinic, this diagnosis could have been missed- well done to him!

The second female patient presented with a rapidly progressive multifocal pneumonia and it was initially considered, by myself and others, to be a post-influenzal staphylococcal pneumonia on clinical grounds alone before any microbiological data were available. It was unsurprising to find all 4 blood culture bottles had grown S. aureus. However, an echocardiogram was performed and this revealed a Ventricular Septal Defect (VSD) with a large vegetation (2cm!!).

Another case of suspected IE was found on a patient with terminal cardiac failure who presented to ER with a fever. He had been developing worsening dyspnoea at rest and rapidly progressive renal failure. The fact that his fingers and toenails had the most splinter haemorrhages I have ever seen (plus Beau's line: arrest of nail growth), a loud cardiac murmur and blood in the urine convinced me he also had IE.

He was transferred to another hospital and so it was not possible to get confirmation of the suspected diagnosis.

Where is all this leading?? Well, in the UK, the diagnosis of infective endocarditis is extremely uncommon. I have personally only seen two cases in seven years and hence, to hear of at least 4-5 cases in under a year has been an eye opener to me.

A patient with a fever, young or old, should always have their finger nails examined for splinter haemorrhages, finger pulps for Osler's nodes, the palms forJaneway Lesions, and if you can do retinal fundoscopy, Roth's spots.

A cardiac murmur may be absent, but in most cases I have seen, they have been present and usually are consistent with regurgitation (systolic or diastolic) from an incompetent destroyed valve. Finding blood in the urine should alert the physician to possible renal infarcts from septic thromboemboli derived from the vegetation. The usual 3 sets of blood cultures must be taken even in the absence of a fever and an high ESR e.g. 80mm/hour, can provide useful clues for making the diagnosis.

A transthoracic echo can sometimes reveal the vegetation, if large enough, but for the small millimeter size vegetations, only an oesophageal echo will do.

The junior doctors need to bear this diagnosis in mind for causes of fever, because if missed, the results can be catastrophic. Examining the hands (particularly the nails) can give the doctor the clue they need to make the diagnosis on physical examination alone, which a CT scan would never see.