Background: Essential Thrombocytosis is a rare chronic myeloproliferative disorder characterized by uninhibited platelet production and a significant risk of arterial thrombosis. When such patients present with thrombotic complications like limb ischemia, the clinical picture may closely resemble peripheral vascular disease.

Case Report: An elderly woman presented with dry gangrene of amputated below-knee stump, treated as a case of Peripheral Vascular Disease previously. Her platelet counts were found to be persistently elevated. A retrospective review of previous laboratory records also revealed unexplained thrombocytosis which was overlooked or missed. A diagnosis of essential thrombocytosis was made by positive JAK2 V617F mutation. Hydroxyurea and anti platelet therapy, resulting in significant improvement.

Discussion: It is essential to recognize Essential Thrombocytosis when presenting as a vascular mimic especially in elderly patients presenting with ischemia,without atherosclerotic risk factors. Early evaluation for myeloproliferative neoplasms through mutation analysis, enables timely cyto-reductive therapy and significantly reduces the risk of further ischemia.

• Essential thrombocytosis

• Peripheral vascular disease

• Chronic limb-threatening ischemia

• Amputation

• Arterial occlusive disease

• Myeloproliferative disorders

Issar P, Shivam, Prajapati P, Bashir I, Shankar R, et al. (2026) Acute Limb Ischemia Unveiling Underlying Essential Thrombocytosis: A Case report. Arch Emerg Med Crit Care 10(1): 1076.

ET: Essential Thrombocytosis; PVD: Peripheral Vascular Disease; CT: Computerized Tomography.

Background

ET is a chronic myeloproliferative neoplasm characterized by sustained thrombocytosis and increased risk of arterial and venous thrombosis [1]. It is a rare disorder with an incidence of 0.38 to 1.7 per 100,000 individuals per annum, with female to male ratio of 2:1 [2,3]. Although, majority of the patients may remain asymptomatic throughout their lives, few present with ischemic complications involving cerebral, coronary or peripheral circulation. Peripheral arterial thrombosis due to ET may be clinically indistinguishable from atherosclerotic peripheral vascular disease, particularly in elderly patients [4]. Failure to recognize ET as an underlying cause of thrombotic events may result in repeated complications, delayed initiation of cyto-reductive therapy and irreversible ischemic injury [5]. We present a case in which long -standing thrombocytosis was overlooked, leading to misdiagnosis as PVD which resulted in not only multiple mutilating surgeries but also loss of limb. Correct diagnosis and treatment resulted in limb preservation.

Case report

An elderly woman presented with dry gangrene of a below-knee amputation stump. Her symptoms started 6 years ago with pain in left knee and black discoloration of left toes. Her medical history included recurrent episodes of lower limb ischemia for which she had been diagnosed and repeatedly treated as PVD. She had undergone multiple mutilating surgeries in the last 6 months, including below knee amputation 2 months ago. During clinical examination, patient was thin built, frail and had a discolored left below knee amputation stump. The stump was dry, skin was thinned out, muscles were atrophied and had a non-healing suture line with sutures in situ. Peripheral pulses in both the lower limbs were diminished (Figure 1A). Right foot also showed signs of arterial insufficiency like dry, pale and cold skin with ulceration and black discoloration of the 1st and 2nd toes (Figure 1B).

Figure 1 (A) below knee amputation stump showing non-healing suture line and sutures in-situ, B. shows thinned-out, discolored skin and muscle wasting in the other foot.

Lab evaluation revealed a platelet count of 1730 x109/ litre with normal haemoglobin and total leucocyte count. Inflammatory markers were within the normal limits. CT angiography of the lower limbs showed significant arterial disease in both limbs (Figure 2A&B). On right side, there was no contrast opacification in the distal anterior tibial, posterior tibial and common peroneal artery. On left side, there was no opacification of long segment of superficial femoral artery with faint reconstitution distally by muscular collaterals, and non-opacification popliteal artery and the rest of distal arteries. 

Clinical picture closely resembled peripheral vascular disease causing arterial insufficiency. But, persistent thrombocytosis could not be explained. Secondary causes of thrombocytosis- including infection, inflammation, iron deficiency, malignancy and post-splenectomy state- were excluded by appropriate lab investigations. Bone marrow examination was done which showed hyper-cellular marrow with remarkable proliferation of megakaryocytes with hyperlobulated nuclei (no evidence of fibrosis/ reduced cellularity) consistent with essential thrombosis. Molecular testing was done for related genetic disorders which revealed positive JAK2V617F mutation confirming the diagnosis of ET.

Figure 2 (A) CT angiography of bilateral lower limbs .A - occluded left superficial femoral artery for a 11cms long segment with partial perfusion by muscular collaterals. Non-opacification of popliteal artery and rest of distal arteries. B- occluded right anterior tibial artery, peroneal artery and posterior tibial artery.

Management and outcome

The patient was initiated on cyto-reductive and anti platelet therapy. Tablet Aspirin and tablet hydroxyurea were started. Over subsequent weeks, her platelet count declined significantly and finally got settled within the normal range (127x109 per litre). Most importantly, ischemic changes at the stump did not progress further and no more tissue loss occurred. In a 6-month follow up, there was no new thrombotic event and the stump remained well-preserved. Platelet counts were stable (146x109 per litre).

This case illustrates several critical clinical lessons. First, essential thrombocytosis can present with arterial thrombosis, closely mimicking peripheral vascular disease. Second, persistent thrombocytosis should never be dismissed without proper evaluation particularly in patients with unexplained ischemic events.

Misdiagnosis of ET as PVD can have devastating consequences (even limb loss as in this patient). Timely diagnosis and appropriate treatment with cyto-reductive therapy can significantly reduce thrombotic risk in ET [6]. This case proves that appropriate treatment not only improved hematologic parameters (platelet count), but also prevented further limb ischemia underscoring the limb-saving potential of timely recognition [7]. Clinician should keep a high index of suspicion for myeloproliferative disorders while evaluating patients with arterial thrombosis disproportionate of established atherosclerotic risk factors. Complete diagnosis can be made with molecular testing for JAK2 CALR and MPL mutation.

To conclude, ET is an uncommon but important and often overlooked cause of arterial thrombosis. Wrong diagnosis as PVD and delayed recognition may result in catastrophic outcomes such as major limb loss. Early evaluation of unexplained thrombocytosis and timely initiation of cyto-reductive therapy can be limb-saving in the management of patients with limb ischemia.

A written, informed consent was obtained from the patient for the publication of his case study.

Availability of Data and Materials

Patient related data will be provided on request.

Authors’ Contributions

PI and PP drafted the manuscript, reviewed the literature and edited the manuscript.RS and IB revised and edited the manuscript. AOS and RS were in charge of the case and reviewed the manuscript.

The authors are thankful to the patient and her family members for their support in publishing this paper.

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