Thursday, 21 February 2008

History Can Be Better Than CT !!

Dear Bloggers

I want to tell you about another real patient case that has been anonymised to show you how history can give the diagnosis better than a CT scan !

An elderly patient was admitted into hospital with a 3-day history of increasing dyspnoea and cough. The patient was normally wheelchair bound following an episode of Stevens-Johnson Syndrome several years before although she was able to walk a few steps to visit the toilet. However, in the 3-day period, because of breathlessness the patient was unable to walk at all.

The cough was productive and the sputum was said to be clear and there was no apparent bloody tinge to the sputum or any haemoptysis.

However, prior to admission, the patient developed a high fever of over 39 degrees which prompted the admission into the hospital.

The patient admitted that she had been losing weight and had a reduced appetite for at least 6 months.

The patient was a heavy smoker and had been so for many years.

The patient denied any chest pain (pleuritic) or bone pain.
There were no shaking chills or night sweats.
There were no upper or lower gastrointestinal symptoms, no joint or muscle pains, no genitourinary problems and no cardiac symptoms such as palpitations.

Previous Medical History included the above in addition to type 2 diabetes and hypertension.

The patient was being treated with glimepiride, metformin, enalapril and aspirin.

The was no family history of note and the patient lived with her husband in an apartment block and the elevator was working and they had good family support.

On examination

The patient looked slightly unwell and was sweaty (perspiration on the forehead and a drenched hospital gown) but was conscious and alert. The patient was hot to the touch.

Hands revealed tar staining of the fingers on the right hand consistent with heavy, prolonged cigarette smoking but there was no finger clubbing. There was some mild palmar erythema but no CO2 retention flap.

The pulse was regular, bounding in nature and tachycardic at 110/min. Skin turgor was reduced.
BP was 110/60 supine- a sitting blood pressure to assess for hypovolaemia was not performed.

JVP was not elevated and there were no palpable lymph nodes in the neck or axillae.

Eyes were normal and there was no anaemia, jaundice and no Horner's Syndrome.

Mouth examination revealed a bone-dry tongue and coagulated blood around the gums.

CVS: heart sounds were normal 1 + 2 and no murmurs or added sounds. There was no peripheral oedema.

RESP: respiratory rate was 14 per minute, the chest was hyper-expanded and the trachea revealed the 'tug'-sign consistent with chronic lung disease but it was not deviated.
Percussion was resonant throughout anteriorly and posteriorly.
Auscaultation in fact revealed coarse, wet crackles at the left base and reduced air entry on that side.

ABDO: Abdominal examinaion was soft, non-tender, no hepatosplenomegaly, no renal angle tenderness. A 4-5 cm abdominal aortic aneurysm was identified in the epigastric region- there was an added bruit. The bowel sounds were normal.

Peripheral pulses were normal.

CNS examination was grossly normal.

PNS examination revealed proximal muscle wasting although there was some wasting of the small muscles on the dorsum of both hands.
Tone was within normal limits.
Power was approximately 4/5 throughout.
Reflexes were present in the upper limbs but absent in the lower limbs. There was no muscle fasculation.
Coordination and sensation testing had not been performed.
Babinski examination was normal on the right and equivocal on the left.


From the history and examination it was clear that this patient had an acute illness and a bacterial pneumonia was highly likely.

However, the preceding 6 months of weight loss and reduced appetite plus the evidence of a proximal myopathy made a bronchogenic carcinoma also likely. Ca lung is well established to result in paraneoplastic proximal myopathy.

Examination of the chest Xray on the PACS (electronic radiology) was unrevealing.

Bloods revealed a raised WBC and inflammatory markers plus a raised BUN and normal creatinine which respectively indicated infection and dehydration that were already found through the history and examination.

A senior doctor was not content with the PACS radiograph and asked to see the hard copy plain film because experience showed that more can be seen on the plain film.

Indeed, on looking a the hard copy CXR it was clear that there were several ununited rib fractures, an odd shadow at the hilum on the left side around the area of the aortic knuckle and looking behind the heart shadow there was consolidation.

To the senior physician, it made the suspicion of a bronchogenic carcinoma even more likely.

Review of the CT earlier by the junior doctor had suggested only a consolidation was evident but on review by the senior doctor, with the idea that a malignancy was likely, indeed a malignant neoplasm was identified around the region of the aortic arch.

The moral of the story is that there were two process in play here. Firstly, the acute deterioration with symptoms and signs of a pneumonia. Yes, pneumonia is very common in the elderly but in a chronic smoker, one must always think about malignancy. With the more chronic component of weight loss and appetite loss, a hunt for the malignancy was imperative.

Using a PACS system is excellent as it can be used throughout the hospital and films almost never get lost! However, it depends upon which type of computer screen and resolution whether you can see the problems. If it is a high-tec radiologist high resolution screen then there is usually no problem to identify changes. However, if it is an old LCD screen with poor resolution, covered in dust and finger print marks then I would suggest looking at the plain film every time because otherwise, you will miss important problems.

In this case, the patient had a pneumonia secondary to a malignant tumour that had metastasized to bone. This malignancy had been initially missed, although later picked up by the senior doctor, because the CXR could not be adequately read on the PACS system and moreover, because the history of weight and appetite loss had not been fully appreciated by the junior physician.

The clinical suspicion came from the history and physical examination and the odd shadow around the aortic knuckle confirmed the suspicion. CT gave nicer pictures but did nothing to aid in the diagnosis.

A bit of advice is, try to hold the plain xray film at an angle when looking at the heart shadow because you can sometimes see areas of consolidation show up that had previously been unseen when looking head on. Also, try not to stand so close to the Xray. Sometimes, standing back, you will see the consolidated area literally jump out at you and you will wonder how you missed it in the first place. Lastly, remember that the lungs extend below the upper level of the diaphragm shadows on the CXR-- hence, pneumonia can sometimes be hiding below the diaphragm. CXR reading is an art and it is not simply done before doing a CT !! If you can read the CXR properly, in most cases, you don't need to do a CT especially for pneumonia.

Repeating tests to give you the same answer makes little logical sense and increases radiation exposure and cost.

Please consider not using CT scans when they are not clinically necessary. It should be enough with taking a thorough history, physical examination and a plain Xray film unless there are unusual features that cannot be easily determined or that require more detailed examination.

So, next time you see a smoker with pneumonia, find out if they have symptoms of malignancy e.g. bone pain, weight / appetite loss, symptoms of hypercalcaemia etc and bear that in mind when you look at the CXR !

Have a great weekend!!!

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