as well as the presence of anemia.2 D‐dimers measure a specific type of cross‐linked fibrin degradation, while the elevated levels are indicators of recent clotting activity such as clotting dissemination or intravascular coagulation.
3 Prothrombin time (PT) is the time for blood to clot in a general screen that evaluates factors VII, X, II and II.
4 Activated partial thromboplastin time, also known as A PTT, is a sensitive indicator of coagulation and evaluates additionally to PT factors such as prekallikrein, factors VII, IX and high molecular weight kininogen, and examines how both the intrinsic clotting pathway and the common final pathway are working.
5 No
Comments: Vitamin D is required for regulation of calcium and phosphorus in the body. Its deficiency is common and related to osteoporosis in older patients and rickets in children but not with clotting diseases.
Q3 Which of the drugs below enhance the bleeding?
1 Aspirin
2 Fluconazole
3 Metronidazole
4 Phenytoin
5 Omeprazole
Answers:
1 Aspirin is often used together with warfarin in patients with valve replacement and increases the bleeding tendency, but it is always dependent on the intensity of the treatment.
2 Fluconazole is the drug of choice for various fungal infections. In combination with warfarin, it can increase the hypoprothrombinemic effect of the second drug by interfering with its metabolism and inhibiting the liver enzymes CYP450 2C19 and 3A4.
3 Metronidazole increases the plasma concentration of warfarin by inhibiting the action of CYP450 2CR enzyme that is responsible for the metabolic clearance of the active enantiomers of warfarin.
4 No
5 Omeprazole is sometimes related to an increased action of warfarin, but their interaction seems to have a minor, doubtful or limited clinical significance.
Comments: Phenytoin, a well‐known antiepileptic drug, has a complex interaction with warfarin. It initially increases but later reduces INR after a prolonged application.
2 Blue and/or Black Lesions
Blue and black oral lesions have been characterized by increased pigmentation due to accumulation either of melanin (true) or hemosiderin, metals, chemical coloring agents and drug metabolites (non‐true discoloration) within the oral mucosa and teeth. These lesions may be manifestations of a group of congenital or acquired diseases with traumatic, reactive, neoplasmatic, and infective origin (Figure and 2.0ab).
The most common causes of black or blue pigmentation are listed in Table 2.
Figure 2.0a Blue lesion.
Figure 2.0b Black lesion.
Table 2 The most common causes of blue and black lesions.
| Pigmentation |
| Related to melanin (brown, black lesions)Increased melanin production only Related to race Racial pigmentosawRelated to hormone alterations ChloasmaAddison diseaseEctopic ACTH productionNelson syndromeAcanthosis nigricansLaugier‐Hunziker syndromeLeopard syndromeSpotty pigmentation, myxoma, endocrine overactivity syndromeVon Recklinghausen's diseaseAlbright syndromeRelated to consumption of DrugsFoodsRelated to exposure in sunFrecklesSolar lentiginesRelated to smoking habitsBetel nut chewingSmoker's melanosis Related to inflammationLP metachrosisBMMP metachrosisEM metachrosis Related to various factorsEphelides (simple)Ephelides in Peutz‐Jegher syndrome Increased number of melanocytesLentigines simplexNeviMelanoma Related to hemosiderin (blue, red lesions)AngiomasKaposi's sarcomaEpithelioid angiomatosisEcchymosisHemochromatosis/hemosiderosisBeta thalassemia Related to foreign material (gray, black lesions)ArgyriaHeavy metal poisoning (lead, bismuth, arsenic)Permanganate or silver poisoningTattoos (amalgam, lead pencils, ink, dyes, carbon) |
Case 2.1
CO: A 65‐year‐old woman was referred by her dentist for evaluation of a black discoloration of her buccal mucosae and palate.
HPC: The discoloration was firstly noticed by her dentist during a routine examination for denture replacement one week ago.
PMH: She was a slim woman with dark skin and with no serious medical problems apart from low blood pressure and chronic allergic asthma which were controlled with a special salty diet and systematic steroids respectively. She also suffered from iron deficiency anemia at child bearing age, and had been on iron tablets only on the days of menstruation. Smoking had been stopped from the age of forty.
OE: The intra‐oral examination revealed dark black–bluish discolorations on her buccal mucosae, soft palate and lips (Figure 2.1). This discoloration was diffuse, superficial, and prominent at areas of chronic friction such as at the occlusal line. Similar discolorations were seen on the skin of hands and feet. Fatigue, nausea, or even episodes of fainting during very tiring activities were occasionally reported.
Q1 Which is the possible diagnosis?
1 Racial pigmentation
2 Hemosiderosis
3 Addison's disease
4 Melasma
5 Melanoma
Answers:
1 No
2 No
3 Addison's disease is the cause of the dark pigmentation of her skin and oral mucosa (especially on buccal mucosae) which was attributed to the increased stimulatory action of adrenocorticotropic hormone (ACTH) in the melanocytes, changing the color of melanin pigment to black or dark. This disease is characterized
