What are the two main clinical lab abnormalities associated with magnesium tetany?

Magnesium tetany is primarily characterized by two significant clinical lab abnormalities: hypomagnesemia and hypocalcemia. Hypomagnesemia, or low magnesium levels, can lead to increased neuromuscular excitability, which is often the underlying issue in cases of tetany. Concurrently, hypocalcemia, or low calcium levels, exacerbates neuromuscular irritability and can be associated with magnesium deficiency. This combination of deficiencies creates a clinical picture typical of magnesium tetany, leading to symptoms such as muscle spasms or twitching. Adequate magnesium levels are crucial for maintaining stable calcium levels in the body, so low magnesium often correlates with low calcium.

The other options do not accurately represent the main abnormalities associated with magnesium tetany. Hyperkalemia and hypophosphatemia can arise in various other conditions but are not characteristic of magnesium tetany. Similarly, hypercalcemia and hypermagnesemia indicate excess levels of these minerals, which are not relevant in the context of tetany caused by deficiencies. Normokalemia and hypokalemia do not pertain to the primary metrics associated with magnesium tetany and fail to capture the essential issues related to magnesium and calcium levels.