Pigmented Epithelioid Melanocytoma in a Child: Unusual Clinical Presentation

369 intravenous adenosine is known to adversely cause facial flushing, headache, palpitations, light headedness, dizziness, blurring of vision and nausea, the local pain or discomfort and local flushing are not described. These adverse events were probably caused by intra-arterial injection of adenosine in the given case. In a clinical trial done by Costa et al [6] , adenosine injection in the brachial artery caused increased forearm blood flow by activation of the afferent fibers in the forearm producing sympathetic stimulation in addition to local vasodilator effect. Another clinical trial by Sylven et al [7] reported that, adenosine injection into the brachial artery produced ischemia like pain or discomfort in the forearm. Pain or discomfort began 12 s after administration, reached its maximum after 17 s and disappeared after 40 s. These effects were dose dependant. Due to very short half-life the adverse effects of adenosine quickly wear off when the drug is discontinued [8]. The effects of adenosine can also be quickly interrupted using aminophylline, which acts as an antidote. The high-risk patients for intra-arterial cannulation and drug administration are those who are morbidly obese and have a darkly pigmented skin, in a critical care setting, hypotensive and those with a pre-existing vascular anomaly [2]. Our case probably had an anomalous radial artery termed as antebrachialis superficialis dorsalis radial artery which runs superficially past the radial styloid process-a site that is commonly used for cannulation of one of the terminal branches of the cephalic vein (often referred to as the intern vein) [9,10]. The prevalence of this anomaly is 1%. References 1. Cohen SM. Accidental intra-arterial injection of drugs. 3. ter Schure JM, de Vries TW. Accidental intra-arterial injection of adenosine in a patient with supraventricular tachycardia. injection into the brachial artery produces ischaemia like pain or discomfort in the forearm. Zembowicz et al [1] coined the term PEM for a " low-grade melanocytic tumor with metastatic potential indistinguishable from animal-type melanoma and epithelioid blue nevus ". PEM is a distinct melanocytic tumor occurring in a sporadic setting and in the context of Carney complex. A 10 year-old child was referred for evaluation of a blue-black cutaneous macule found in the right pectoral region. The lesion measured 0.4×0.3 cm. The histology of the lesion showed a densely pigmented dermal nodule with infiltrative borders. The proliferation was composed of epithelioid and spindle melanocytes with heavy pigmentation; atypical cells were present (Fig. …