1/5. Normal pulse oximeter reading in a cyanotic infant.A newborn infant who presented with central cyanosis was found to have hereditary methaemoglobinaemia. The pulse oximeter readings and physical findings were incompatible. Clinical assessment remains an important part in the management of such cases.- - - - - - - - - - ranking = 1keywords = physical (Clic here for more details about this article) |
2/5. Congenital methemoglobinemia: a rare cause of cyanosis in the newborn--a case report.cyanosis is a physical finding that can occur at any age but presents the greatest challenge when it occurs in the newborn. The cause is multiple, and it usually represents an ominous sign, especially when it occurs in association with neonatal sepsis, cyanotic congenital heart disease, and airway abnormalities. cyanosis caused by abnormal forms of hemoglobin can also be life-threatening, and early recognition is mandatory to prevent unnecessary investigations and delay in management. Abnormal hemoglobin, such as hemoglobin m, is traditionally discovered by electrophoresis, so the newborn screen, which is mandatory in several states, is a useful tool for the diagnosis. Although acquired methemoglobinemia, caused by environmental oxidizing agents, is common, congenital deficiency of the innate reducing enzyme is so rare that only a few cases are documented in the medical literature around the world. We present a neonate with cyanosis as a result of congenital deficiency of the reduced nicotinamide adenine dinucleotide-cytochrome b5 reductase enzyme. This infant was found to be blue at a routine newborn follow-up visit. sepsis, structural congenital heart disease, prenatal administration, and ingestion of oxidant dyes were excluded as a cause of the cyanosis by history and appropriate tests. Chocolate discoloration of arterial blood provided a clue to the diagnosis. A normal newborn screen and hemoglobin electrophoresis made the diagnosis of hemoglobin m unlikely as the cause of the methemoglobinemia (Hb A 59.4%, A2 1.8%, and F 38.8%). Red blood cell enzyme activity and dna analysis revealed a homozygous form of the cytochrome b5 reductase enzyme deficiency. He responded very well to daily methylene blue and ascorbic acid administration, and he has normal growth and developmental parameters, although he shows an exaggerated increase in his methemoglobin level with minor oxidant stress such as diarrhea.- - - - - - - - - - ranking = 1keywords = physical (Clic here for more details about this article) |
3/5. Permanent retinal damage following massive dapsone overdose.A massive dose of 7.5 g of 4,4'-diamino, diphenyl sulphone (dapsone) taken as a suicide attempt in a patient on long-term therapy for tuberculoid leprosy resulted in permanent bilateral retinal necrosis, previously unreported side effect of this drug. The patient developed a severe haemolytic anaemia, methaemoglobinaemia, and acute renal failure requiring peritoneal dialysis. It is proposed that the retinal damage was due to a combination of severe hypoxaemia and the physical effects of red cell fragmentation producing vascular occlusion in the macular and perimacular region, with consequent ischaemic necrosis.- - - - - - - - - - ranking = 1keywords = physical (Clic here for more details about this article) |
4/5. An unusual cause for cyanosis.cyanosis is a common physical sign in clinical medicine. Cardiac or respiratory conditions are the usual causes. We report a patient with an unusual cause for cyanosis and highlight the salient clues that lead to the diagnosis.- - - - - - - - - - ranking = 1keywords = physical (Clic here for more details about this article) |
5/5. methylene blue-induced phototoxicity: an unrecognized complication.OBJECTIVE. To describe photosensitization after prenatal exposure to a toxic amount of methylene blue and to alert pediatricians that, in a review of the literature, photosensitization (which this dye is capable of) has not been reported as a complication of prenatal exposure. DESIGN AND patients. A descriptive report of physical findings and significant laboratory tests in a very low birth weight preterm infant with prenatal exposure to methylene blue and a comparison of this reported case with previously described patients' complications and treatment. SETTING. Neonatal intensive care unit. INTERVENTION. Monitoring of laboratory tests to assess for methylene blue toxicity: two exchange transfusions for methemoglobinemia, hemolytic anemia, and hyperbilirubinemia; phototherapy for hyperbilirubinemia; and pathologic examination of skin bullae. RESULTS. Within hours of exposure to phototherapy, redness developed on all exposed areas of the patient's skin (which was initially deep blue), followed by bullae and desquamation of about 35% of the total skin surface area. The desquamation of erythematous areas continued even after discontinuation of phototherapy. Complete re-epithelialization was attained by 3 weeks of age. In addition to this newly observed complication, the patient had other previously described toxic effects. CONCLUSION. We have reported a previously unrecognized complication associated with high prenatal exposure to methylene blue and treatment with phototherapy. methylene blue phototoxicity may be related to the high prenatal dose of the dye relative to patient's small size and young gestational age.- - - - - - - - - - ranking = 1keywords = physical (Clic here for more details about this article) |