So Diagnosis Was Not Confirmed

Revision Part 1

Case 1:

A19 year old male admitted with acute onset generalized weakness for 1 day duration. He woke up with diffuse weakness; no anti-gravity strength in arms (he cannot lift an object; severe weakness), unable to get out of bed. Proximal > distal weakness; bilaterally symmetrical on both sides. He denied diplopia, dysphagia, dysarthria, facial droop, drooling or change in level of consciousness.

PMH: similar episode in Feb 2013, admitted to local hospital for 4-5 days, Diagnosed with GBS (Guillain-Barre syndrome), treated with plasmapheresis, no LP/ EMG

So diagnosis was not confirmed

O/E Vitals stable. General physical exam unremarkable

Neurological exam

Mental status: AAO * 4

Speech: fluent with comprehension intact

CN 2-12: PERRLA, EOM – full, normal facial sensation and symmetry,

1 Normal facial strength, hearing intact, equal palatal elevation and tongue midline; so all cranial nerves were intact and normal.

Motor: Power: 2+ ULL & LL

Sensory: Intact

DTX: Diminished

Planter: Down going.

Hb - 14.6, WBC 6.1 Glucose 51 mmol/l

Plt count 215 Calcium 9.3 mg/dl Sodium 143 mmol/l Magnesium 2.0 mg/dl K 1.3 mmol/l Phosphorus 2.4 Chloride 110 mmol/l CK 493 BUN 13 Aldolase 15.7 Creatinine 0.83 TSH: 2.082 free T3 – 3.8, free T4 – 0.9 , Urine electrolytes: NAD

So what’s the problem here? This is a young man with a similar attack year and half ago, he has diffuse muscle weakness in upper and lower limbs especially in the anti-gravity muscles.

Cranial nerves exam is normal and there’s no diplopia in other words he does not have myasthenia gravis.

2 He does not have dysphagia or dysarthria which means that the brainstem is normal. So someone can say that there’s no diplopia, dysphagia, dysarthria then the brainstem is out.

So what’s the other differential diagnosis?

Is it in the central nervous system? Here all the cranial nerves are normal, there’s nothing wrong in the brain itself.

Is it in the peripheral nervous system? It’s a possibility, here the reflexes are diminished but the sensation is intact so the peripheral nerves are fine because you cannot have a pure motor weakness with peripheral nerves disease and this patient have pure motor weakness.

Is it in the neuromuscular junction?

Or is it in the muscle? If you look at the investigations of the patient you can see that the potassium is very low and the CK is raised while all other investigations are normal.

This is not uncommon case in Saudi Arabia, do you know about “Hypokalemic periodic paralysis”?

It’s a condition in which you get severe hypokalemia and complete paralysis of the whole body and this condition usually occurs after

3 consuming a good carbohydrate rich meal; you eat a big meal and then you become flat.

But it still could be a Guillain-Barre syndrome we didn’t ignore that completely but the important thing here is to differentiate from is it a central nervous system or is it peripheral nervous system or is it neuromuscular or is it in the muscle?

Here predominantly the problem is the muscle weakness with intact all cranial nerves.

So the differential diagnosis:

1- Periodic hypokalemic paralysis.

2- Myasthenia gravis.

3- Guillain-Barre syndrome.

What disease (s) should be excluded? You should exclude:

1- Paraneoplastic syndrome.

2- …..

4 It’s not a typical question and you don’t have to answer it 100% here if you said it’s a generalized muscle weakness then you answered 50 – 60%.

Case 2:

76 year old woman is admitted unwell with vomiting and is found to have low blood pressure. She had recently been given diclofanac for back ache. Her blood results are:

Na+ 137 mmol/l

K+ 6.7 mmol/l

Urea 223 mmol/l

Cratinine 609 µmol/l

Cl- 95 mmol/l

HCO3- 24 mmol/l

So what are the abnormal results here?

Potassium is very high, urea is also high, cratinine is also very high so what’s the cause here? She’s vomiting??

The only history here that she had a back ache and she was given diclofanac which is a non-steroidal anti-inflammatory drug.

5 So which system, which part of the body affected the most? Which system is failing?

It’s the kidney of course, the kidney is gone.

This patient has an acute renal failure which happened abruptly so what’s the cause?

She was given a drug and it’s well known that non-steroidal anti- inflammatory drugs can cause acute tubular necrosis, interstitial necrosis or acute renal failure so it’s drug induced renal failure.

We all agree that there are abnormal kidney function tests so it’s the kidney and cannot be anything else.

So the question is “what’s the cause”? Wither underlying disease, drugs, SLE, I don’t care about that but what I want not to miss is the abnormality of these findings.

So we say this is acute renal failure with high potassium, creatinin and urea.

What’s the threat of life here? Which of these elements is a killer? Potassium of course as it’ll affect the heart, it’ll cause heart asystole and arrest so the biggest concern here is the potassium.

6 So how to deal with that? Of course calcium resonate is the correct answer but how can you move the calcium from blood to the cells?

You also know that when you are treating a patient with DKA you give potassium, why?

To enter the cell with the insulin, can you do the same here? Yes, you can give glucose and that will move with insulin potassium from blood into the cells.

It’s a very serious risk here so you can give insulin with glucose, you can give calcium resonate which is a correct answer.

Anything else?

Of course you can do dialysis, it’s the easiest way.

The important thing is that you be able to pick the abnormality as this is an easy question.

Case 3:

33 year old f female presented with malaise, joint discomfort and general feeling unwell. She was diagnosed Graves’ disease four years ago and rendered euthyroid (she was treated and became normal) (Normal thyroid function). She had also suffered from celiac disease since her teens. She had no respiratory complaint. She had recent chest X-ray which showed right pleural effusion of moderate size.

Pleural aspiration was performed which showed:

7 Pleural fluid sample

Total protein 33.2 g/l

LDH 287 IU/l

pH 7.036

Microbiology Nil seen

Amylase 65U/l

Rheumatoid factor 557IU/l

She is a young lady with a past history of 2 autoimmune diseases; Grave’s disease and coeliac disease so she is an autoimmune problem, maybe it’s not the answer here but this is how to read the case scenario, it’s how to approach the problem.

Now this patient is asymptomatic and the chest X ray was done routinely to discover the pleural effusion.

First of all you must read this pleural effusion to know is it transudate or exudate? Here the protein is so high so it’s exudate also LDH is so high and it’s the most sensitive test for pleural effusion exudate.

8 So what’s the other abnormality here? It’s the rheumatoid factor, it’s very very high.

Now what’s the cause of this pleural effusion?

She has joint pains so rheumatoid arthritis is an excellent answer, anything else? Systemic lupus is also a 100% correct answer because she’s an autoimmune patient and she’s a good case for SLE as well as for rheumatoid arthritis.

But rheumatoid arthritis here is more the correct answer because of the very high rheumatoid factor, in SLE she may have high rheumatoid factor as well so the correct answer here is either SLE or rheumatoid arthritis although nothing was given in the history.

Case 4:

45 year old lady is complaining of generalized aches and pains for several months. She still is menstruating regularly. Her blood tests include following:

Calcium 2.99 mmol/l

Phosphate 0.44 mmol/l

9 ALP 158 U/l

Albumin 41 g/l

What’s the abnormal here? This is high calcium.

This is a 45 year old lady with high calcium “moans, groans and pains” it’s a typical symptom of hyperparathyroidism.

Now what’s the cause of hypercalcemia?

1- Multiple myeloma, it’s very high calcium.

2- Sarcoidosis.

3- Malignancies in the body.

4- Metastasis in the bone or anywhere else.

5- Granulomatous diseases as TB.

So anyone who would say that he’ll treat it with phosphate I’ll accept that because you don’t know more than that.

Now what essential test would you request? We have to look for a cause for high calcium.

If you suspect hyperparathyroidism you do parathyroid hormone, if someone said I’ll do plasma Electrophoresis it’ll be alright.

10 What I want to know from you have to give me one test, something which will lead to the cause.

Case 5:

60 years old diabetic presented with this lesion of her leg

What is the name of this lesion?

Candidiasis? It’s a possibility but it’s typically “necrobiosis lipoidica diabeticorum”.

11 What’s the recommended treatment? A good control of diabetes because I want to know that you know the problem and going to deal with it.

Case 6:

32 year female presented with fever & weight loss

Describe radiological findings

What’s the abnormal here? You should read the whole chest film PA VIEW:

 The trachea looks central.

12  Heart looks normal in shape and size.

 What’s abnormal? You have all this reticular shadows and nodules all over the lungs,

Bronchitis does not give a picture like this while miliary TB is a possibility.

So in other words what is the differential diagnosis of miliary shadow of the lung?

1- Miliary TB

2- Sarcoid

3- Diffuse metastatic lesions.

4- Lymphomas

5- Silicosis

But if you were asked to give 2 only then the differential diagnosis is TB and sarcoid, they are very common and they present like that.

There’s a hint here “fever and weight loss”, so if you have a fever in young patient so it’s mostly TB.

13 Case 7:

What’s the abnormality present in ECG recording?

You have abnormal complexes here, some complexes look normal and others look abnormal.

What kind of abnormality? They are all abnormal QRS complexes, see in between normal rhythm so you have got multiple QRS complex abnormality in between normal rhythm.

So it’s ventricular Tachycardia but I don’t expect you to answer this but I want you to say that this is abnormal QRS complexes.