Looking for external clues
The first step in a post-mortem is to examine the patient for clues as to the cause of death. What did the pathologist, Dr Alison Clureo find with Chris Smith?
Alison - This is a gentleman in his eighth decade of life; he had a history of ischaemic heart disease. So this means had hardening of the coronary arteries that supply his heart so he was at risk of having a heart attack. He had a history of a condition called chronic obstructive pulmonary disease which is where the lungs may have either bronchitis, or a condition called emphysema, which can be related to smoking. And, on the background of that, a condition called pulmonary hypertension where, because of the lung disease, the heart begins to fail trying to pump blood through these diseased lungs. He also had a history of type 2 diabetes, which was treated with medication rather than insulin injections.
Chris - Is there anything else, in terms of information that you're given, that might inform something you go looking for? Do you learn about the occupation of a person, or where they lived, where they came from, that kind of thing that might bias your terms of thinking like well, I should look for x, y, or z.?
Alison - Well, we also know that there's a possibility that this man may have been exposed to asbestos in the past. So, given that history in combination with lung disease, we would want to make sure this wasn't an industrial acquired lung disease related to inhalation of asbestos fibres.
Chris - So, having acquainted yourself with this gentleman - what happened to him in the past, his past medical history and also his occupational history - what do you do next?
Alison - So, my next procedure is to examine him externally in the first instance to see if there are any clues, and to make sure that I am about to autopsy the correct person.
Chris - Shall we do that?
Alison - Yes. On examination, he has several significant findings, In particular, he has a condition called clubbing of the fingernails and of the toenails. This condition is commonly seen in people with chronic lung diseases.
Chris - They do indeed look almost like the end of a drum stick, when you get to the end where the drumstick hits the surface of the drum it's sort of rounded curve shape. It's not the normal shape of a fingernail and all of his fingers look like that.
Alison - Yes. The whole nail curve rounds and you see this in the toes, to a lesser extent, but it's much more obvious in the fingernails. The other significant finding on external examination is that he has swelling of his lower legs, a condition that we describe medically as pitting oedema. So the lower legs, right up to the knees are swollen and I can actually indent the tissues because he has fluid in those tissues.
Chris - You've pressed, just gently, over the skin of his shin and you've left a finger impression there, which sits there for a while, rather like a footprint in sand, and then it slowly comes back out again, and that's because of fluid?
Alison - That's fluid retention in the tissues.
Chris - Anything else?
Alison - He has some areas of hemorrhagic bruising and some areas of skin tearing on his upper arms. I'm just wondering, although I don't have this information quite to hand, whether he had had some steroid treatment for his chronic airways disease. Steroid treatment, long term, can cause thinning of the skin and, in this instance, it's quite possible that the injuries that we're seeing are related to him having very fragile skin, subsequent to him having been on long term steroid therapy for lung disease.
Chris - Now with me in the studio to unpick some of these external clues are:
Dr James Rudd, he's a cardiologist at Addenbrooke's hospital and a Senior Lecturer at Cambridge University. Also Dr Helen Simpson, she's an Endocrinologist - someone who understands how the body's endocrine glands work. And Also, Dr Prina Ruparelia who's a Respiratory Consultan, also from Addenbrooke's.
Now Prina - Alison mentioned steroid treatment there. What is chronic obstructive airways disease?
Prina - It's really an umbrella term. It's generally related to smoking; the smoking causes inflammation in the airways which damages the alveoli, which are the air sacks, and it causes bronchitis, which is production of excess mucus. So the people that have this condition will often have a cough and they will have symptoms of breathlessness.
Chris - What about the hands? Because on of the other things we spotted was that his fingers have this characteristic clubbing. How common is that and why does that happen, do we know?
Prina - The actual mechanism is not really clear but it's often a sign of another condition in the body. So, when we're looking a lung conditions, it can be a sign of what we call a suppurative lung condition, which means a pus forming lung condition such as a lung abscess or cystic fibrosis.
Chris - And how common is this sort of presentation with chronic obstructive pulmonary disease? Is this a common phenomenon?
Prina - You wouldn't see clubbing in chronic obstructive pulmonary disease, so there must be something else that is causing that.
Chris - So we've still got something to look for. We know that COPD isn't the only thing going on in this gentlemen then based on what you've told us.
Helen - We know that the gentleman had type 2 diabetes. What is type 2 diabetes?
Helen - Type 2 diabetes is the most common cause of diabetes with about 90% of the people in the UK who have diabetes, having type 2 diabetes. And it's where the body gets insulin resistant or can't react so well to the insulin that the body makes, and is what we think of as being related to obesity and a more sedentary lifestyle.
Chris - This gentleman wasn't particularly overweight. Is that a common way for diabetes to present then, or do some people start a bit overweight and then become thinner?
Helen - So, when you're diagnosed with diabetes, one of the symptoms can be weight loss, so becoming very thirsty, passing a lot of urine, and losing weight. We don't know how long he'd had diabetes. If it was a new diagnosis he may have been losing weight or could have lost weight from another underlying pathology or condition. The other thing is he'd been taking steroid tablets and this can actually cause type 2 diabetes. It could be a drug cause and that may have been accounting for some of the sugar problems.
Chris - Ah right. So he could have a diabetic problem because of the steroids he was taking for his chest problem?
Helen - He could have, yes.
Chris - Why should it be bad to have high blood sugar? Why is that a problem?
Helen - It can cause some symptoms in itself. So it can make you feel thirsty, pass too much urine, you can lose some weight, and cause some problems with vision, the lens in the eye can get a little bit cloudy. But also it leads to long term complications and we split these into medical word, macrovascular - so big blood vessel complications and small blood vessel complications. People with type 2 diabetes are five times more likely to die of heart problems or vascular problems than the general population without diabetes.
Chris - James - Helen has mentioned that diabetic patients are at greater risk of damage to their blood vessels. What's the relevance here? This gentleman has a history of heart failure. Why might this be relevant and, also, what's the basis for the pitting oedema, the skin changes that Alison remarked on?
James - So diabetes, as you've said Chris, is associated with high levels of glucose in the bloodstream, and this can damage the inside of the arteries causing a process we call atherosclerosis. If the arteries to the heart have been narrowed by atherosclerosis, the pumping power of the heat is reduced, and this can mean the blood can build up in tissues of the body where it normally wouldn't accumulate so, for example, patients can get swelling of the legs.
Chris - The high pressure what, pushes fluid out of the blood vessels and into the tissue and that's why you get swelling and that's why, when we put our fingers on the skin, we could make those little indentations because we were literally pushing fluid out of the way?
James - That's exactly right. The condition is called heart failure. If the patient's heart failure is treated, then we often use the amount of peripheral oedema, the amount of swelling of the legs, as a sign that treatment is working. This will tend to get better over a few days or weeks.