Q. 2. Describe the laboratory investigations for bleeding and clotting disorders.
Ans. Various laboratory diagnostic tests for bleeding and clotting disorders are as follows:
Investigation of disordered vascular haemostasis
Disorders of vascular haemostasis may be due to vascular permeability, reduced capillary strength and failure to contact after injury.
Bleeding time
• This simplest test is based on the principle of formation of haemostatic plug following standard incision on volar surface of forearm and the time the incision takes to stop bleeding is measured the test is dependent upon capillary function as well as on platelet number and ability of platelets to adhere to form aggregates.
Hess capillary resistance test (Tourniquet test)
• This test is done by placing sphygmomanometer cuff to the upper arm and raising the pressure in it between diastolic and systolic for 5 min.
• After deflation, the number of petechia appearing in the next 5 min in 3 cm area over the cubital fossa is counted.
• Presence of more than 20 petechiae is considered a positive test. The test is positive in increased capillary fragility as well as in thrombocytopenia.
Investigation of platelet and platelet function
Special tests
Tests for coagulative defect
Q. 3. What are the aetiological factors for the spontaneous bleeding from gingiva? Describe the oral manifestations of myelogenous leukaemia.
Or
How do you manage a case of myeloid leukaemia patient visiting dental hospital.
Ans.
The various causes of bleeding in the oral cavity are as follows:
Local causes
• Postextraction, postsurgical, posttraumatic.
• Infections—viral, bacterial fungal, parasitic and spirochete.
• Oral ulcerative lesions—stomatitis, glossitis, etc.
• Oral exophytic soft tissue lesions—pyogenic granuloma, pregnancy tumour.
• Local irritants leading to gingivitis and periodontitis.
• Rupture of blood containing bulla.
• Congenital hamartomas—haemangioma, hereditary haemorrhagic telangiectasia.
Haemorrhage due to platelet disorders
Haemorrhage due to coagulation diseases
Haemorrhage due to systemic diseases
Leukaemia
Leukaemia is a disease characterized by the progressive over production of white blood cells, which usually appear in the circulating blood in an immature form.
Classification
• Depending on the onset and the course of the leukaemia it is classified as:
• Depending on the type of cell of origin leukaemia is also classified into:
Acute and chronic leukaemias are broadly classified as:
Aetiology
Clinical features
Acute leukaemia
• Acute lymphoblastic leukaemia is common in children while acute myeloid leukaemia is common in adults.
• Characterized by weakness, fever, headache, petechial or ecchymotic haemorrhages in the skin and mucous membranes.
• Lymphadenopathy is often the first sign of the disease.
• Gingival bleeding, epistaxis, haemorrhage may occur due to thrombocytopenia.
• Bleeding may occur due to disseminated intravascular coagulation (DIC), which is mainly in patients with acute promyelocytic leukaemia.
• Hepatomegaly, splenomegaly, gum hyperplasia, stomatitis, sternal tenderness, enlargement and infiltration of skin may be seen.
Chronic leukaemia
• Disease is present before the symptoms are seen.
• Patient may appear with excellent health or exhibit emaciation suggestive of a chronic debilitating disease.
• Lymph node enlargement common in CLL but uncommon in CML.
• Splenomegaly and hepatomegaly are fully developed due to protracted course of the disease.
• Enlargement of salivary glands and tonsils leading to leukaemic infiltration and xerostomia.
• Petechiae, ecchymosis of skin. Papules, pustules, bullae, areas of pigmentation, herpes zoster, itching and burning sensations are also seen.
Oral manifestations
Diagnosis
a. Peripheral blood examination reveals the presence of blast cells with high, low or normal total leukocyte count.
b. There is also the evidence of anaemia and thrombocytopenia.
c. The bone marrow examination shows hypercellularity along with the presence of >20 % leukaemic blast cells.
d. Cytochemical staining, cytogenetics and immune-phenotyping of the cells help in differentiating different types of leukaemia.
Treatment
Supportive treatment
Specific treatment
• The objective of specific treatment is to eliminate leukaemic cells without affecting the normal cells. However, the therapy may be associated with high morbidity and mortality. Hence, the decision to administer a specific therapy to a particular patient is based on the age, type of leukaemia and the presence of other associated illnesses.
Chemotherapy
Radiotherapy
Bone marrow transplantation
• If a patient relapses after chemotherapy, remission is difficult to induce, then bone marrow transplantation is advised in such cases.
Q. 4. Classify anaemias. Discuss in detail the oral manifestations, diagnosis and management of pernicious anaemia.
Or
Define and classify anaemias. Discuss in detail about iron deficiency anaemia.
Or
Classify anaemias. Describe clinical features and laboratory diagnosis of iron deficiency anaemia.
Ans. Anaemia is defined as an abnormal reduction in the number of circulating red blood cells, the quantity of haemoglobin and the volume of packed red cells in a given unit of blood. The normal haemoglobin level varies from 14 to 16 g/dl in the adult male and 12 to 14 g/dl in the female.
Classification
Anaemia has been traditionally classified into:
According to the morphology (MCV, MCH and MCHC) into the following types:
However, the recent classification is based on reticulocyte index, which is a measure of RBC production:
Aetiologic classification of the anaemias
II. Deficiency of haemopoietic factors
IV. Anaemia due to systemic infections or systemic disorders
• Anaemia due to chronic infection
• Anaemia due to chronic renal disease
V. Anaemia due to bone marrow infiltration
VI. Anaemia due to increased red cell destruction (haemolytic anaemia)
Pernicious anaemia
(Vitamin B12 deficiency, Addisonian anaemia)
Pernicious anaemia is a type of a chronic progressive, megaloblastic anaemia of adults and is caused by deficiency of intrinsic factors in stomach.
Clinical features
• Occurs rarely before 30 years of age and increases in frequency with advancing age.
• No racial predilection, in other countries except in US females are more commonly affected.
• The four major cardinal features of pernicious anaemia are:
c. Neurologic and gastrointestinal symptoms
d. A fatal outcome unless the patient receives life-long injections of vitamin B12.
• Generalized weakness, fatigue, headache, palpitation, nausea, vomiting, anorexia and diarrhoea.
• Shortness of breath, dyspnoea, loss of weight, pallor and abdominal pain.
• Patients have smooth, dry and yellow skin.
• Neurological manifestations include tingling sensation in hands and feet, paraesthesia of extremities due to peripheral nerve degeneration.
Oral manifestations
Histopathology