What does a urine specific gravity of 1.156 indicate?

Urine Specific Gravity of 1.156 Indicates Severe Dehydration

A urine specific gravity of 1.156 is significantly elevated above the normal range (1.005-1.030) and indicates severe dehydration requiring immediate medical attention and rehydration. 1

Normal Range and Clinical Significance

• Normal urine specific gravity ranges from 1.005 to 1.030, with optimal hydration typically showing values between 1.010-1.025 1
• Values >1.030 indicate significant dehydration, and a reading of 1.156 is dramatically above this threshold 1
• First-morning urine specific gravity should typically be 1.025 or higher after overnight fluid restriction, serving as a useful screening measurement of renal concentrating ability 2

Clinical Implications of Severely Elevated Specific Gravity (1.156)

• This extremely high specific gravity (1.156) indicates profound dehydration that requires immediate medical intervention 1
• Such severe dehydration can impair physical performance and cognitive function 1
• At this level, there is significant risk of acute kidney injury due to pre-renal causes 3
• This value is well beyond the range typically seen even in cases of significant dehydration, suggesting possible laboratory error or extremely concentrated urine 3

Common Causes of Severely Elevated Specific Gravity

• Severe fluid volume depletion from:
  • Excessive sweating without adequate replacement (heat exposure, intense physical activity) 1
  • Vomiting or diarrhea leading to fluid loss 3
  • Inadequate fluid intake over an extended period 1
  • Fever causing increased insensible fluid losses 4
• Diabetes mellitus with glucosuria can contribute to elevated specific gravity, though typically not to this extreme level 5
• Certain medications, particularly diuretics, can increase urine concentration 1

Management Recommendations

• Immediate rehydration is necessary, preferably with oral fluids if the patient can tolerate them, or intravenous fluids if oral intake is inadequate 1
• Monitor for signs of hemodynamic instability (tachycardia, hypotension) which may accompany severe dehydration 3
• Assess for underlying causes of the severe dehydration 1
• Recheck specific gravity after initial rehydration to ensure improvement 6
• Target achieving a urine specific gravity below 1.020 to indicate adequate rehydration 1

Important Considerations and Pitfalls

• A specific gravity this high (1.156) is unusual and may warrant verification with repeat testing to rule out laboratory error 3
• Using specific gravity as the sole indicator of kidney function without considering other parameters can be misleading 1
• Consider checking serum electrolytes, BUN/creatinine ratio, and osmolality to assess the systemic impact of severe dehydration 7
• In patients with diabetes, elevated specific gravity may be due to both dehydration and glucosuria, requiring assessment of both conditions 5
• A BUN/creatinine ratio >15 along with high urine specific gravity (>1.010) has been associated with early neurological deterioration in acute ischemic stroke patients 7