Sheila Dawling

At a Glance Sickle cell anemia, or homozygous hemoglobin S, may be expected in any person with anemia (hemoglobin < 0 g/dL), abnormal peripheral blood findings, a family history of sickle cell trait or sickle cell anemia, and/or a positive newborn screen for sickle cell anemia. The sickle mutation is most commonly found in persons…

At a Glance Ethanol intoxication should be considered in any patient in whom there is unexplained loss of consciousness, altered sensorium, or onset of seizures. A toxic dose is 5g/kg in an adult and 3 g/kg in a child. Ingestion of ethanol is common and is estimated to be responsible for some 600,000 emergency department…

At a Glance Isopropanol (2-propanol; IPA) intoxication should be considered in any patient in whom there is rapid unexplained loss of consciousness or central nervous system (CNS) depression, particularly with a history of a liquid ingestion and fruity aroma on the breath. The demonstration of ketonemia and ketonuria without an anion gap metabolic acidosis should…

At a Glance Methanol intoxication is not common but is frequently severe or fatal. Rapid recognition and prompt treatment, especially of the acidosis, are crucial to outcome if permanent visual impairment and brain damage are to be prevented. In the absence of an exposure history, methanol intoxication is difficult to diagnose. Clinical manifestations are usually…

At a Glance Ethylene glycol poisoning is not common and is often unintentional, as it is a colorless slightly viscous sweet-tasting liquid. Rapid recognition and prompt treatment are crucial to prevent renal failure and other serious sequelae. In the absence of an exposure history, ethylene glycol intoxication is difficult to diagnose. Clinical manifestations are usually…

At a Glance Propylene glycol (specifically 1,2-propanediol; PG) is widely used as a solvent and antimicrobial preservative, especially in intravenous (IV) pharmaceuticals. Poisoning is, therefore, usually iatrogenic, under-appreciated, and under-diagnosed. Since it is considered less toxic than ethylene glycol, it has been substituted for it in some antifreeze, and the incidence of toxic ingestion is…

At a Glance Coinheritance of hereditary persistence of fetal hemoglobin (HPFH) with homozygous SS disease should be suspected in a patient with known Sickle Anemia who has a less severe clinical presentation than expected or a family history of the same. These patients have a modestly elevated hemoglobin F (up to about 30% of the…

At a Glance Coinheritance of an α-thalassemia with homozygous SS disease should be suspected in a patient with known Sickle Anemia who has a less severe clinical presentation than expected or who has a family history of the same. These patients have a modestly elevated hemoglobin F (<20% of the total hemoglobin) in the absence…

At a Glance A ß-thalassemia may be coinherited with both sickle trait or homozygous sickle disease and will reduce the amount of ß-globin chain production. The presentation is highly variable, depending on the severity of the ß-thalassemia (from mild dysregulation through to null production and whether it is coinherited with Sickle Cell Anemia or with…

At a Glance Compound heterozygosity for hemoglobin O-Arab and hemoglobin S is rare but should be suspected in patients with known sickle trait who have an unexpectedly severe course reminiscent of homozygous Sickle Cell Anemia or who have a family history of the same. Patients with hemoglobin S/O-Arab have a modestly elevated hemoglobin F (5-18%…

At a Glance Compound heterozygosity for hemoglobins D-Los Angeles and S should be suspected in a patient with known sickle trait who has a moderate anemia (7-10 g/dL), an unexpectedly severe clinical picture, or a family history of the same. The patient’s peripheral smear shows sickle cells, target cells, and increased polychromasia. This combination of…

At a Glance Compound heterozygosity for Hemoglobin C and Hemoglobin S should be suspected in a patient with known sickle trait who has an unexpectedly severe clinical picture or who has a family history of the same. Patients with hemoglobin S-C follow a clinical course similar to, but milder than, Sickle Cell Anemia (see chapter…

At a Glance A family history of anemia in the absence of iron deficiency should prompt consideration of a hemoglobinopathy, and a number of these appear in the differential diagnosis. Hemoglobin Köln is an inherited mutation in the ß-globin gene. It is predominantly confined to persons of German and Dutch descent. Hemoglobin Köln is an…

At a Glance A family history of anemia in the absence of iron deficiency should prompt consideration of a hemoglobinopathy, and a number of these appear in the differential diagnosis. The Lepore hemoglobins are inherited mutations, resulting from δß-gene fusion products. Lepore-Boston is the only mutation to occur with any frequency and is mostly confined…

At a Glance A family history of anemia in the absence of iron deficiency should prompt consideration of a hemoglobinopathy, and a number of these appear in the differential diagnosis. The hemoglobin O-Arab is an inherited mutation in the ß-globin gene. Persons of Balkan or North African black descent are more likely to carry this…

At a Glance A family history of anemia in the absence of iron deficiency should prompt consideration of a hemoglobinopathy, and a number of these appear in the differential diagnosis. Hemoglobin G-Philadelphia can arise from one of two different mutations in the α-globin gene. Although both produce the same protein, the mutations occur in different…

At a Glance A family history of anemia in the absence of iron deficiency should prompt consideration of a hemoglobinopathy, and a number of these appear in the differential diagnosis. Hemoglobin Ds are inherited mutations in the ß-globin gene, of which it is by far the most common is D-Los Angeles (also known as D-Punjab).…

At a Glance A family history of anemia in the absence of iron deficiency should prompt consideration of a hemoglobinopathy, and a number of these appear in the differential diagnosis. Hemoglobin C is an inherited mutation in the ß-globin gene. Persons of West African descent are much more likely to carry this mutation, which is…

At a Glance A family history of anemia in the absence of iron deficiency should prompt consideration of a hemoglobinopathy, and a number of these appear in the differential diagnosis. Hemoglobin E is an inherited mutation in the ß-globin gene. Persons of SE Asian decent frequently carry this mutation, which is the 4th most common…

At a Glance Sickle cell trait may be expected in any person with a family history of sickle cell trait or sickle cell disease. This mutation is commonly found in persons of African, Middle Eastern, or Mediterranean descent, but rare cases have been reported in most ethnic groups. It is found in approximately 8% of…