Wallach's Interpretation of Diagnostic Tests: Pathways to Arriving at a Clinical Diagnosis (1041 page)

   Sarcoidosis

   
Malignant tumors

   Increased in approximately 50% of patients with various solid carcinomas, especially in advanced stages.

   In patients with cancer, a higher LD level generally indicates a poorer prognosis. Whenever the total LD is increased and the isoenzyme pattern is nonspecific or cannot be explained by obvious clinical findings (e.g., MI, hemolytic anemia), cancer should always be ruled out. LD is moderately increased in approximately 60% of patients with lymphomas and lymphocytic leukemias and approximately 90% of patients with acute leukemia; degree of increase is not correlated with WBC counts; levels are relatively low in lymphatic types of leukemia. LD is increased in 95% of patients with chronic myelogenous leukemia, especially LD-3.

   
Diseases of muscle

   Marked increase of LD-5, likely due to anoxic injury of striated muscle

   Electrical and thermal burns and trauma; marked increase of total LD (about the same as in MI) and LD-5

   
Renal diseases

   Renal cortical infarction may mimic pattern of AMI. Rule out renal infarction if LD-1 (>LD-2) is increased in the absence of MI or anemia or if increased LD is out of proportion to AST and ALP levels.

   May be slightly increased (LD-4 and LD-5) in nephrotic syndrome. LD-1 and LD-2 may be increased in nephritis.

   
Miscellaneous conditions

   These conditions may be related to hemolysis, involvement of the liver, striated muscle, or heart

   Various infectious and parasitic diseases