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Back to Topics<<<< Some hereditary disoerders especially hemolytic anaemias are associated with or connected to splenomagaly and hypersplenism. The disease may be regarded as autosomal dominant traits. The essential lesion is an increase in permeability of the Red Blood Cell’s (RBC) membrane to sodium. As sodium leaks into the RBC, its osmotic pressure rises, it swells, becomes more spherical and more fragile. In this condition the energy and oxygen requirements of RBC increases. In spleen there is deficiency of both glucose and oxygen in the pulp so large number of RBCs are destroyed. Splenectomy reduces RBC destruction though doesn’t correct the membrane defect and lessens anaemia. The circulating bilirubin remains unconjugated to glucoronic acid and is attaches to albumin. This is not excreted through urine hence called Acholuric jaundice. Clinical Features: The patient is present with anaemia and jaundice. Pigment stones in the gall bladder may also be encountered. RBC count falls down the two millions during attacks. Such attacks are characterized by pain in abdomen, nausea, vomiting, pyrexia, pallor and jaundice. Investigations On examination splenomegaly is observed. Liver becomes palpable and chronic ulcers of legs in adults are seen. After attacks, reticulocyte count is increased. Faecal urobilirubin is increased as most of the urobilirubin is excreted by this route. Thalassaemia is the result of defect of haemoglobin (Hb) peptide chain synthesis, which is transmitted as dominant trait. The disease is a group of related diseases – α, β and γ depending on the peptide chain whose rate of synthesis is reduced. Most patients suffer from β – type in which reduction in β – chain synthesis results in decrease in HbA. In addition intercellular precipitate (Heinz body) contributes to premature RBC destruction. Clinical Features: Anaemia, jaundice and splenomegaly are the prominent features. Those patients with Thalassaemia (homozygous) show signs in the first year of life i.e. retarded growth, enlarged head with slanting eyes and depressed nose, leg ulcers, jaundice and abdominal distension due to splenomegaly. Investigations: RBCs are small, thin and misshapen so we have characteristic resistance to osmotic lysis. In severe cases nucleated RBCs and immature RBCs are seen. Diagnosis is finally confirmed by the Hb electrophoresis. Sickle cell anaemia is hereditary haemolytic anaemia, in which normal HbA is replaced by HbS. HbS molecule crystallises when O2 tension is reduced. As a result this distorts and elongates the red cells. This increased blood viscosity obstructs the flow of blood through both “Open” and "Closed” circulations within the spleen; and through other blood vessels. Splenic microinfarcts, splenomegaly and later autosplenectomy develop. This is associated with reduced antibody production and a reduced ability to filter bacteria especially Streptococcus Pneumoniae in spleen. Clinical Features: Mostly the patients are asymptomatic. Depending on the vessel affected by vascular occlusion, patients may have bone and/or joint pain, neurological abnormalities, skin ulcers, abdominal pain due to visceral blood stasis. Investigations: Sickle shaped RBCs can be seen on blood films but now it has been replaced by Hb electrophoresis Treatment: Splenectomy is only indicated here Is defined as “The focal haemorrhage in the skin”. It is due to the development of antibodies, which destroy the patient’s own platelets or it may be due to:
Purpuric patches (ecchymosis) occur in skin and mucous membrane. A tendency of spontaneous bleeding occur from mucous membrane e.g. epistaxis in women to menorrhagia and prolonged bleeding from minor wounds. Urinary, gastrointestinal and intracranial haemorrhage is rare. Cutaneous ecchymosis is found on examination and tourniquet test is positive. Investigation:
Corticosteroids (Azathioprine) Splenectomy (in adults, menarche) Blood transfusion Common lymphomas characterized with presence of typical multinucleated giant cells. The effects on different areas are as follows: Neck region: 60-80% Axilliary region: 15% Inguinal region: 12% Clinical Features: Presented by painless and progressive enlargement of lymph nodes primarily detected in cervical group on one side then on the other associated with or without generalized symptoms as weigh loss, malaise, fever or pruritis. Pressure effects such as superior vena caval obstruction from enlarged mediastinal lymph nodes may follow. Bone pain especially in the back due to vertebral collapse secondary to bony metastasis. Unexplained symptom is the affected region after alcohol intake (Splenomegaly and Hepatomegaly). With dissemination, bony metastasis, anaemia and pancytopenia may develop. Jaundice due to excessive haemolysis of RBC or diffused liver involvement is seen. Stages: Clinical Stages:
It is a syndrome to the development of overwhelming infections, which include fulminant bacteraemia, pneumonia and meningitis. According to Singer’s data post-splenectomic sepsis occur in 4.2% of cases with 2.5% of mortality rate. The incidence of complications in is 100 times higher in patients with haemolytic anaemia, Hodgkin’s disease and some hereditary disorders. In some cases it may be fulminant and occurs after 24 hours of operation. Main signs are fever, disorientation, nausea, vomiting, headache, confusion, shock and comma. Blood cultures reveal Streptococcus Pneumoniae, H. Influenzae and E.Coli. That is why after splenectomy we must give antibiotics as an active treatment for prophylaxis and polyvalent vaccines, which contain H. Influenzae and E.Coli etc.. This article has been written by Dr. M. Javed Abbas. If you have any comments please do not hesitate to sign my Guest Book. 21:07 21/12/2002 |