What are common causes of increased anion gap metabolic acidosis? Can someone have an increased anion gap without being in metabolic acidosis? How does the measurement of the urinary anion gap help narrow the differential diagnosis of normal anion gap metabolic acidosis? What are the major types of renal tubular acidosis, and how are they diagnosed? How is urinary chloride used in the diagnosis of metabolic alkalosis? How is the delta gap used to diagnose complex acid-base disorders? What two systems regulate acid-base homeostasis? What are the causes of respiratory alkalosis? What are the causes of respiratory acidosis? What are the causes of metabolic alkalosis? What are the causes of metabolic acidosis?                          What are the four most common causes of high AG metabolic acidosis? What toxins can lead to high AG metabolic acidosis? What are the potential causes of normal anion gap metabolic acidosis?