creatinine_clearance_calculator.py•10.6 kB
"""
Creatinine Clearance Calculator (Cockcroft-Gault Equation)
"""
from typing import Dict, Any
from medcalc import (
BaseCalculator,
CalculatorInfo,
Parameter,
ParameterType,
ValidationResult,
CalculationResult,
register_calculator
)
from medcalc.utils import round_number
@register_calculator("creatinine_clearance")
class CreatinineClearanceCalculator(BaseCalculator):
"""肌酐清除率计算器实现 (Cockcroft-Gault 方程)"""
def get_info(self) -> CalculatorInfo:
return CalculatorInfo(
id=2,
name="Creatinine Clearance (Cockcroft-Gault)",
category="nephrology",
description="Calculate creatinine clearance using the Cockcroft-Gault equation",
parameters=[
Parameter(
name="age",
type=ParameterType.NUMERIC,
required=True,
unit="years",
min_value=1,
max_value=120,
description="Patient age in years"
),
Parameter(
name="sex",
type=ParameterType.CHOICE,
required=True,
choices=["Male", "Female"],
description="Patient sex"
),
Parameter(
name="weight",
type=ParameterType.NUMERIC,
required=True,
unit="kg",
min_value=1,
max_value=500,
description="Patient weight in kg"
),
Parameter(
name="height",
type=ParameterType.NUMERIC,
required=True,
unit="cm",
min_value=30,
max_value=300,
description="Patient height in cm"
),
Parameter(
name="creatinine",
type=ParameterType.NUMERIC,
required=True,
unit="mg/dL",
min_value=0.1,
max_value=20.0,
description="Serum creatinine concentration in mg/dL"
)
]
)
def validate_parameters(self, params: Dict[str, Any]) -> ValidationResult:
errors = []
warnings = []
# 检查必需参数
required_params = ["age", "sex", "weight", "height", "creatinine"]
for param in required_params:
if param not in params:
errors.append(f"Missing required parameter: {param}")
if errors:
return ValidationResult(is_valid=False, errors=errors)
# 验证年龄
try:
age = float(params["age"])
if age < 1 or age > 120:
errors.append("Age must be between 1 and 120 years")
except (ValueError, TypeError):
errors.append("Age must be a valid number")
# 验证性别
if params["sex"] not in ["Male", "Female"]:
errors.append("Sex must be 'Male' or 'Female'")
# 验证体重
try:
weight = float(params["weight"])
if weight < 1 or weight > 500:
errors.append("Weight must be between 1 and 500 kg")
if weight > 200:
warnings.append("Weight is very high, please verify")
except (ValueError, TypeError):
errors.append("Weight must be a valid number")
# 验证身高
try:
height = float(params["height"])
if height < 30 or height > 300:
errors.append("Height must be between 30 and 300 cm")
except (ValueError, TypeError):
errors.append("Height must be a valid number")
# 验证肌酐
try:
creatinine = float(params["creatinine"])
if creatinine < 0.1 or creatinine > 20.0:
errors.append("Creatinine must be between 0.1 and 20.0 mg/dL")
if creatinine > 10.0:
warnings.append("Creatinine level is very high")
except (ValueError, TypeError):
errors.append("Creatinine must be a valid number")
return ValidationResult(
is_valid=len(errors) == 0,
errors=errors,
warnings=warnings
)
def calculate(self, params: Dict[str, Any]) -> CalculationResult:
# 获取参数值
age = float(params["age"])
sex = params["sex"]
weight = float(params["weight"])
height = float(params["height"])
creatinine = float(params["creatinine"])
# 计算BMI
height_m = height / 100 # 转换为米
bmi = weight / (height_m * height_m)
# 确定体重状态
if bmi < 18.5:
weight_status = "underweight"
elif 18.5 <= bmi <= 24.9:
weight_status = "normal weight"
else:
weight_status = "overweight/obese"
# 计算理想体重 (IBW)
height_inches = height / 2.54 # 转换为英寸
if sex == "Male":
ibw = 50 + 2.3 * (height_inches - 60)
else:
ibw = 45.5 + 2.3 * (height_inches - 60)
# 确定调整体重
if bmi < 18.5:
# 体重不足：使用实际体重
adjusted_weight = weight
elif 18.5 <= bmi <= 24.9:
# 正常体重：使用理想体重和实际体重的较小值
adjusted_weight = min(ibw, weight)
else:
# 超重/肥胖：使用调整体重公式
adjusted_weight = ibw + 0.4 * (weight - ibw)
# 性别系数
gender_coefficient = 1.0 if sex == "Male" else 0.85
# 计算肌酐清除率 (Cockcroft-Gault)
creatinine_clearance = ((140 - age) * adjusted_weight * gender_coefficient) / (creatinine * 72)
creatinine_clearance = round_number(creatinine_clearance)
# 生成详细解释
explanation = self._generate_explanation(
age, sex, weight, height, creatinine, bmi, weight_status,
ibw, adjusted_weight, gender_coefficient, creatinine_clearance
)
return CalculationResult(
value=creatinine_clearance,
unit="mL/min",
explanation=explanation,
metadata={
"age": age,
"sex": sex,
"weight": weight,
"height": height,
"creatinine": creatinine,
"bmi": round_number(bmi),
"weight_status": weight_status,
"ideal_body_weight": round_number(ibw),
"adjusted_weight": round_number(adjusted_weight),
"gender_coefficient": gender_coefficient
},
warnings=[]
)
def _generate_explanation(self, age: float, sex: str, weight: float, height: float,
creatinine: float, bmi: float, weight_status: str,
ibw: float, adjusted_weight: float, gender_coefficient: float,
creatinine_clearance: float) -> str:
"""生成详细的计算解释"""
explanation = "The formula for computing Cockcroft-Gault is given by:\n"
explanation += "CrCl = ((140 - age) × adjusted weight × gender_coefficient) / (serum creatinine × 72)\n\n"
explanation += f"Where the gender_coefficient is 1 if male, and 0.85 if female.\n"
explanation += f"The serum creatinine concentration is in mg/dL.\n\n"
explanation += f"Patient Information:\n"
explanation += f"- Gender: {sex.lower()}, gender coefficient = {gender_coefficient}\n"
explanation += f"- Age: {age} years\n"
explanation += f"- Weight: {weight} kg\n"
explanation += f"- Height: {height} cm ({height/2.54:.1f} inches)\n"
explanation += f"- Serum creatinine: {creatinine} mg/dL\n\n"
# BMI计算和体重状态
explanation += f"BMI Calculation:\n"
explanation += f"BMI = weight(kg) / [height(m)]² = {weight} / [{height/100:.2f}]² = {bmi:.1f} kg/m²\n"
explanation += f"The patient's BMI is {bmi:.1f}, indicating they are {weight_status}.\n\n"
# 理想体重计算
height_inches = height / 2.54
explanation += f"Ideal Body Weight (IBW) Calculation:\n"
if sex == "Male":
explanation += f"For males: IBW = 50 kg + 2.3 kg × (height in inches - 60)\n"
explanation += f"IBW = 50 + 2.3 × ({height_inches:.1f} - 60) = {ibw:.1f} kg\n\n"
else:
explanation += f"For females: IBW = 45.5 kg + 2.3 kg × (height in inches - 60)\n"
explanation += f"IBW = 45.5 + 2.3 × ({height_inches:.1f} - 60) = {ibw:.1f} kg\n\n"
# 调整体重选择
explanation += f"Adjusted Weight Selection:\n"
if bmi < 18.5:
explanation += f"Because the patient is underweight, we use the patient's actual weight "
explanation += f"({weight} kg) as the adjusted weight for the Cockcroft-Gault equation.\n\n"
elif 18.5 <= bmi <= 24.9:
explanation += f"Because the patient has normal weight, we use the minimum of the ideal body weight "
explanation += f"and the patient's actual weight.\n"
explanation += f"Adjusted weight = min({ibw:.1f}, {weight}) = {adjusted_weight:.1f} kg\n\n"
else:
explanation += f"Because the patient is overweight/obese, we use the adjusted body weight formula:\n"
explanation += f"ABW = IBW + 0.4 × (actual weight - IBW)\n"
explanation += f"ABW = {ibw:.1f} + 0.4 × ({weight} - {ibw:.1f}) = {adjusted_weight:.1f} kg\n\n"
# 最终计算
explanation += f"Cockcroft-Gault Calculation:\n"
explanation += f"CrCl = ((140 - {age}) × {adjusted_weight:.1f} × {gender_coefficient}) / ({creatinine} × 72)\n"
explanation += f"CrCl = ({140 - age} × {adjusted_weight:.1f} × {gender_coefficient}) / {creatinine * 72}\n"
explanation += f"CrCl = {creatinine_clearance} mL/min\n\n"
explanation += f"The patient's creatinine clearance is {creatinine_clearance} mL/min."
return explanation