PERIPHERALIA

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A colleague came in to see me recently, as a patient, 
complaining of left sided abdominal pain, loss of appetite and 
episodes of vomiting.  She has a family history of diverticulitis 
and she was tender over the descending colon. I said that I 
thought that she had diverticulitis but the vomiting did not 
quite fit in with this single diagnosis and that she might have 
Saint’s triad.  The problem then was that neither of us could 
remember what Saint’s triad was so I had to look it up.

Charlie Saint established the first department of surgery 
at Groote Schuur in Cape Town.  His triad proposes that 
diverticulosis, gall bladder disease and hiatus hernia may 
occur together in the same patient.  He emphasised the 
importance of considering the possibilities of more than one 
diagnosis in a patient.  This is particularly relevant to general 
practice in this modern day due to the ageing populations 
and their multiple organ failures as well as the many 
medications that we have to juggle with each day.  In the 
past it has been proposed that these three conditions may 
occasionally occur together because of lack of fibre in the 
diet or a connective tissue disorder or even obesity, which 
may be a common denominator although these causational 
theories would need further scientific scrutiny.  

One could almost make up one’s own triads.  I like the idea 
of Ellis’s Triad of tension headache, irritable bowel syndrome 
and lumbar backache.  In the tangled web of general practice 
one can also throw in a troubled life, the gene pool and the 
rand-dollar exchange rate.

In this complexity of human relationships and uniqueness, 
one could apply the same reasoning to our interpretations 
of the patient’s histories and stories. This fallacy of accepting 
a one-dimensional view of the patient is fittingly called “The 
Danger of the Single Story” by the author Chimamanda Ngozi 
Adichie. We may stereotype the patient into one incomplete 
category according to his or her origin, religion or gender. 

This also appears to fit in with the current experience of 
psychiatric illness in general practice in that single diagnoses 
rarely fit an individual patient’s circuitry.  Perhaps every 
diagnosis in psychiatry should have after it “spectrum 
disorder” despite the DSM V trying to put every human 
behaviour into boxes.

The opposing view to this complexity theory comes partly 
under the aphorism “common diseases occur commonly” 
and one should look for the simple explanation first.  Enter 
a 14th century Franciscan friar called William from the village 
of Ockham in Surrey, England.  His theory was called Occam’s 
Razor because he advised us to “shave away” with a razor 

unnecessary or less common diagnoses or assumptions 
and stick to less complex alternatives. This involves quite 
complicated philosophical arguments and is difficult to 
reduce into compact statements but the gist of the argument 
may be expressed as “if you have two theories that both 
explain the observed facts, then you should use the simplest 
until more evidence comes along”.  This is also known as the 
Principle of Economy referring to both clinical reasoning and 
the cost of excessive investigations looking for rarer causes 
of presentations.

Now enter, stage right, John Hickam, who was a professor 
of medicine at Indiana University in the United States of 
America.  He came in on the side of Charlie Saint with the 
counterargument that doctors should not assume or look for 
a single diagnosis for multiple symptoms, but that “a man can 
have as many diseases as he damn well pleases”. 

We are thus left with two counterbalancing principles. On the 
one hand there is Occam’s Razor.  This is adapted in medicine 
into what is called diagnostic parsimony which asks us to 
accept the simplest explanations as well as not accepting 
all the additional assumptions to cover all the symptoms or 
signs. We should strive for the fewest possible causes that will 
account for all the symptoms.  On the other hand, Hickam’s 
Dictum indicates that a patient is more likely to have several 
common diseases rather than a single rarer disease that may 
explain the multiple symptoms.

I find that many more diagnoses have become available 
to us in the last few decades and I am presented with a list 
of diagnoses for a patient from diabetes, hypertension, 
dyslipidaemia, hypothyroidism through to osteoporosis 
and general anxiety disorder (both mine and the patient’s).  
One of the other problems is the prioritization of these 
modern medical conditions and their treatment, which is a 
conversation for another day. 

Now that I have confused myself with complex alternatives, 
single assumptions and competing hypotheses, I will retire 
to the tea room and indulge myself in a higher intellectual 
activity – watching the cricket on the telly.

Chris Ellis is a family physician in Pietermaritzburg, 
KwaZulu-Natal

50 of his previous columns have now been put into book form 
called: 
Peripheralia. Digressions from Medical Practice. 
It is available online at www.amazon.com  ebooks. 

E mail: cristobalellis@gmail.com

Saint’s Triad, Occam’s Razor  
and Hickam’s Dictum