A Case of Phlegmasia Cerulea Dolens.

Phlegmasia cerulea dolens (PCD) is a rare but severe manifestation of extensive deep vein thrombosis (DVT) characterized by near-complete venous outflow obstruction, resulting in massive limb swelling, cyanosis, and risk of venous gangrene. Early recognition and prompt management are essential to prevent limb loss and life-threatening complications. A 55-year-old man presented with sudden-onset swelling, pain, and numbness of the left lower limb that began approximately four hours before presentation. The symptoms initially progressed rapidly and then stabilized without significant further deterioration. The patient reported a sensation of skin tightness but denied limb coldness. He was able to move the affected limb, although movement was limited by pain and swelling. Before symptom onset, he had normal mobility and remained fully independent in daily activities. He denied chest pain, dyspnea, or other cardiopulmonary symptoms. His medical history was significant for hypertension, and his brother had a history of DVT. On examination, the left lower limb was markedly swollen, tender, and demonstrated bluish discoloration with tense skin. Capillary refill time was prolonged, and distal pulses were initially diminished before becoming non-palpable. The limb was not cold, and there was no objective sensory deficit, although the patient reported paraesthesia. Laboratory investigations demonstrated leukocytosis and markedly elevated D-dimer levels. Doppler ultrasonography revealed extensive occlusive thrombus involving the left common femoral and superficial femoral veins extending into the iliac vein. Further imaging confirmed extensive iliofemoral DVT with cranial propagation into the infrarenal inferior vena cava and associated segmental and subsegmental pulmonary embolism. Following vascular surgery consultation, a working diagnosis of PCD was made. The patient was started on therapeutic anticoagulation with apixaban. Due to the family history of venous thromboembolism, thrombophilia screening was arranged with plans for repeat testing after three months. An outpatient echocardiogram was also requested.