Marriage made in heaven? - Part 2 (Concluding part)

“To confess ignorance is often wiser than to beat about the bush with a hypothetical diagnosis.”  Sir William Osler

Inherited giant platelet disorders are extremely rare; they are usually grouped into following categories.

1. Glycoprotein abnormalities-Bernard soulier syndrome, velocardiofacial syndrome
2. Platelet membrane defect-Montreal platelet syndrome
3. alpha granule defect-Gray platelet syndrome
4. with abnormal neutrophilic inclusions-May-Hegglin anamoly, sebastian syndrome
5. With systemic manifestations-Epstein syndrome, Fetchner syndrome
6. No specific abnormalities-Mediterranean macrothrombocytopenia

Now, if you are overwhelmed with this exhaustive list, even I am! I am sure all those students preparing for their speciality or sub speciality entrance exams will be very familiar with these syndromes as our exam system expects us to mug up these and considers us not fit if you aren't able to remember one (enough of cribbing).

Summary of this exhaustive list is described in this article on "Inherited giant platelet disorders"

To simplify it, causes 1 to 5 have some structural defect leading to platelet aggregation, they have variable bleeding symptoms and have some associated abnormalities. Key factor being all of these syndromes present early in life. 6th cause is seen in Mediterranean population is benign large platelets without any bleeding symptoms.

Considering all these points, the old couple did not fit into any of the disorders mentioned above.

Giant platelets, low platelet counts and no bleeding symptoms. It did seem really cosmic to leave it at that. My search for the common factor was on!

The common factor I found was that they were "Chatterjees' and Mukherjees' from Kolkota, West Bengal"

The diagnosis was "HARRIS PLATELET SYNDROME"
It is a newly described entity, in the year 2002 Naina et al. described a new syndrome, asymptomatic constitutional macro thrombocytopenia (ACMT) characterized by mild to severe thrombocytopenia, giant platelets [Mean platelet volume (MPV) >10 fL] with normal platelet functions without any bleeding symptoms in blood donors from West Bengal.It was renamed as Harris platelet syndrome in 2005.The incidence is supposed to be as high as 30%.

At present the diagnosis of HPS is made by ascertaining the ethnicity of the patient, as well as assessing for conditions causing acquired thrombocytopenias, and  excluding the known inherited giant platelet disorders(IGPD).

As reported in one of the pathology journal, this condition is mostly unrecognised and under diagnosed.It is very important that we diagnose these patients, especially if they are from this particular Indian subcontinent region to avoid unnecessary further investigations and also inappropriate treatment with steroids, spleenectomy, etc..

With global migration; it is no longer seen only in specific locus, it can be seen in any part of the world and needs to be recognised. From what I learnt there are very few studies done; we need to further understand the patho-physiology of this particular condition.

In last 2 months I diagnosed another 2 patients with HPS! All you need to do is ask them their names (!!), thrombocytopenia, giant platelets and no bleeding symptoms.

As for my elderly couple who taught me this; they have undergone their surgeries with no bleeding complications.

Here are few more links for those interested
Harris Platelet Syndrome: The Need to Recognise the Entity.
Platelet and red blood cell indices in HPS.