[Diagnosis of alpha-1 antitrypsin deficiency: limitations of rapid diagnostic laboratory tests]. / Diagnóstico del déficit de alfa 1-antitripsina: limitaciones de las pruebas de laboratorio de diagnóstico rápido.

Hereditary alpha-1-antitrypsin (α1-AT) deficiency predisposes to pulmonary emphysema. The objective of this study is to demonstrate the limitations of some laboratory methods used in the study of the deficiency, and which may produce errors in interpretation and detection of uncommon alleles. Two clinical cases are described: the index patient, who had pulmonary emphysema with α1-AT levels less than 12 mg/dL, was erroneously classified as a homozygote of the normal allelic variant PI MM using a rapid genotype method; the mother of the patient, asymptomatic, with low levels (60 mg/dL), was also classified as PI MM. The gene sequencing classified the index patient as a carrier of the PI Clayton null allele and PI Mmalton deficient. The mother was a PI Clayton/PI heterozygote carrier. These results highlight the difficulties in diagnosing the deficiency, as the well as the need to reach a consensus on methods for this study.

[Hepatopulmonary syndrome in a patient with adenocarcinoma of the colon metastatic to the liver and no apparent chronic liver disease]. / Síndrome hepatopulmonar en paciente con adenocarcinoma de colon con metástasis hepáticas y sin hepatopatía crónica conocida.

Hepatopulmonary syndrome consists of a clinical triad: arterial blood deoxygenation, intrapulmonary vasodilation, and liver disease. Both acute and chronic cases of this syndrome have been reported, and the most common cause is cirrhosis. The principle disease mechanism is dilation of the pulmonary blood vessels causing alterations in gas exchange. Increased pulmonary production of nitric acid has been implicated as the primary pathogenic mechanism of vasodilation although it has also been associated with imbalance between vasodilators and vasoconstrictors. We describe the case of a patient with hepatopulmonary syndrome and adenocarcinoma of the colon with metastases to a previously healthy liver.