Arsenical Keratosis Workup

Updated: Apr 02, 2018
  • Author: Chih-Shan Jason Chen, MD, PhD; Chief Editor: Dirk M Elston, MD  more...
  • Print

Laboratory Studies

Chemical analysis of arsenic levels in tissue, hair, or nails is possible, but levels may be normal if exposure is not recent. Arsenic levels in hair and nail samples represent exposure in an immediate past period of time. These levels are prone to include contamination of external arsenic. [32]

Blood arsenic level, spot, or 24-hour urine arsenic level adjusted with creatinine are commonly used for detecting arsenic toxicity. However, arsenic depletes rapidly; if the ingestion was not recent, the arsenic levels may be normal in blood and urine. Recent intake of a large volume of seaweed in the diet may affect the arsenic level. [32] Drinking water arsenic levels should be measured if water is the suspected source of exposure.

The complete blood cell count may reveal anemia, leukopenia, and thrombocytopenia. Red blood cells may show cloverleaf nuclei when systemic symptoms are present.

Blood sugar levels may be necessary to rule out arsenic-associated type 2 diabetes. [33]

Renal and liver function tests should be ordered to rule out insidious damage from arsenic toxicity.


Imaging Studies

Imaging studies are not recommended in a standard workup for arsenical keratoses unless internal malignancy or metastatic disease is suspected after taking a thorough history and completing a physical examination.


Other Tests

Patients with chronic arsenicalism may present with changes on ECG. They may also present with polyneuropathy and changes evident on electromyelography.



A skin biopsy may help establish the diagnosis of arsenical keratosis and rule out the diagnosis of skin cancer.


Histologic Findings

Arsenical keratoses show thick, compact hyperkeratosis and parakeratosis similar to hypertrophic actinic keratoses. Some epidermal keratinocytes may show atypia histologically. [34] The presence of numerous vacuolated keratinocytes and the absence of solar elastosis are suggestive of arsenical keratoses, but these findings are not absolute criteria.