The calculator in question is the Diagnostic Criteria for Severe Malaria. This is a set of criteria used to diagnose severe malaria, a potentially life-threatening condition caused by the Plasmodium falciparum parasite. The criteria are applicable to patients of all ages who present with symptoms suggestive of malaria, particularly in endemic regions or in individuals with a travel history to such areas.

The clinical utility of this calculator is to aid in the early identification of severe malaria, which requires immediate treatment to prevent complications such as cerebral malaria, severe anemia, renal failure, and death. The criteria include signs such as impaired consciousness, prostration, multiple convulsions, deep breathing, circulatory collapse, pulmonary edema, abnormal bleeding, jaundice, hemoglobinuria, and significant laboratory abnormalities.

There are no specific exclusion criteria for the use of these diagnostic criteria. However, they may not be applicable in patients without exposure to malaria-endemic regions or in those with other conditions that can mimic the symptoms of severe malaria. It's also important to note that a negative malaria test does not exclude the diagnosis in severely ill patients, especially if there is a high suspicion of malaria.

Diagnostic criteria for severe malaria

# Criteria
 A. Prostration/impaired consciousness
B. Multiple convulsions
C. Pulmonary edema (oxygen saturation < 92% with respiratory rate > 30/min or confirmed radiologically)
D. Compensated shock (capillary refill >= 3 sec or temperature gradient on the leg without hypotension)
E. Decompensated shock (systolic blood pressure < 70/80 mmHg in children/adults with impaired perfusion)
F. Significant bleeding
G. Jaundice (bilirubin > 50 mcmol/L) with a parasite count > 100,000/mcL
H. Severe anemia (hematocrit < 15-20% and hemoglobin <= 7/5 g/L in adults/children <= 12 years of age) with a parasite count > 10,000/mcL
I. Hypoglycemia (glucose < 2.2 mmol/L)
J. Acidosis (arterial pH < 7.25 or bicarbonate < 15 mmol/L or venous plasma lactate >= 5 mmol/L)
K. Renal impairment (creatinine > 265 mcmol/L or urea > 20 mmol/L)
L. Hyperparasitemia (>= 10%)

# Conditions
- A or B or C or D or E or F or G or H or I or J or K
- true