A patient with lymphoma who is known to excrete 1.5 g urinary protein per day has a negative dipstick evaluation for urinary protein. The reason for the seeming inconsistency is 

A 75-year-old female nursing home resident is brought to the emergency department because of increas- ing obtundation. She is found to communicate poorly. Brief physical examination reveals diminished skin tur- gor. Blood pressure is 100/60, pulse 120, respiratory rate 20, and temperature 37 C (98.6 F). Blood tests reveal the following serum electrolytes: sodium 160 mmol/L, po- tassium 5.0 mmol/L, bicarbonate 30 mmol/L, chloride 110 mmol/L. The most appropriate management at this time would include administration of 5% dextrose in 

Laboratory evaluation of a 19-year-old man being worked up for polyuria and polydipsia yields the follow- ing results:



Serum electrolytes (mmol/L): Na 144; K 4.0; 

Cl 107; HCO 3 25

BUN: 6.4 mmol/L (18 mg/dL)

Blood glucose: 5.7 mmol/L (102 mg/dL) 

Urine electrolytes (mmol/L): Na 28; K 32 

Urine osmolality: 195 mosmol/kg water 



After 12 h of fluid deprivation, body weight has fallen by 5%. Laboratory testing now reveals the following:



Serum electrolytes (mmol/L): Na 150; K 4.1; Cl 109; HCO 3 25

BUN: 7.1 mmol/L (20 mg/dL)

Blood glucose: 5.4 mmol/L (98 mg/dL) 

Urine electrolytes (mmol/L): Na 24; K 35 

Urine osmolality: 200 mosmol/kg water 



One hour after the subcutaneous administration of 5 units of arginine vasopressin, urine values are as follows:



Urine electrolytes (mmol/L): Na 30; K 30 

Urine osmolality: 199 mosmol/kg water



The likely diagnosis in this case is 

A 70-year-old man with diabetes mellitus and hypertension has the following serum chemistries:



Electrolytes (mmol/L): Na 138; K 5.0; Cl 106; HCO 3 20

Glucose: 11 mmol/L (200 mg/dL) 

Creatinine: 176 ’mol/L (2.0 mg/dL)



Which of the following may contribute to worsening hyperkalemia? 

A 40-year-old male alcoholic presents with a 6-day history of binge drinking. Serum chemistry tests reveal the following: 



Electrolytes (mmol/L): Na 145; K 5.0; Cl 105; HCO 3 15

BUN: 7.1 mmol/L (20 mg/dL) 

Creatinine: 133 ’g/L (1.5 mg/dL) 

Glucose: 9.6 mmol/L (172 mg/dL) 



The nitroprusside (Acetest) agent gives a minimally positive result. Optimal therapy to ameliorate the patient’s acid-base disorder would include 5% dextrose in