Splenomegaly

Schistosomiasis

This is prevalent in Africa (particularly around the Nile delta), Asia and South America. It is caused by infection with Schistosoma mansoni in nearly 75 per cent of cases and by Schistosoma haematobium in the remainder. Splenic enlargement is produced by hyperplasia which is induced by phagocytosis of disintegrated worms, ova and toxins, and by portal hypertension which is the result of hepatic fibrosis.

Clinical features

Splenomegaly arising from schistosomiasis can occur at any age and is more prevalent in males. The degree of splenic enlargement reflects the extent of hepatic fibrosis and may be massive.

Investigations

The urine and faeces are examined for ova. Liver function tests reveal a varying degree of hepatic impairment. A hypochromic anaemia is always present.

Treatment

Successful medical treatment of established cases does not result in regression of the splenomegaly. Removal of the painful and bulky spleen is indicated where there is no evidence of hepatic or renal insufficiency. If ascites is present, a portosystemic shunt should be combined with splenectomy.

Tropical splenomegaly

Massive enlargement of the spleen occurs frequently in the tropics, for example in malaria (especially in children), kala­azar and schistosomiasis (see above). In parts of Africa and New Guinea splenomegaly cannot be fully attributed to these diseases because tropical splenomegaly is restricted to only a few adults in areas where malaria is endemic. The most likely explanation is an abnormal immune response to malaria or unusual species of plasmodia. Malnutrition may also be a factor and there is a high incidence in lactating women.

The spleen is grossly enlarged (2000—4000 g). This is associated with anaemia due to shortened red cell life and thrombocytopenia due to splenic sequestration of platelets, which respond to splenectomy. Splenectomy is indicated for those disabled by anaemia or by the weight of an enormous spleen. Splenectomy reduces immunity to malaria and there­fore antimalarial chemotherapy (e.g. proguanil) should follow splenectomy in malaria endemic areas and be maintained for life.

Hypersplenism due to portal hypertension

Splenomegaly invariably accompanies portal hypertension. This splenic enlargement results in thrombocytopenia (due to splenic sequestration of platelets) and granulocytopenia. These are permanently relieved when splenectomy accom­panies operation for the relief of portal hypertension. Shunt surgery alone does not have the same effect.

Felty’s syndrome

A moderate number of patients with chronic rheumatoid arthritis develops mild leucopenia; in a few of these, neutropenia becomes extreme and is usually associated with enlargement of the spleen; this combination is referred to as ‘Felty’s syndrome’. A remarkable characteristic of this syndrome is that the leucopenia and splenic enlargement are apparently unrelated to the severity of the arthritic changes; indeed, in some instances the arthritis has begun to improve or has become quiescent by the time the low white cell count and the splenomegaly become unmistakable. In those cases in which the arthritis is slight but the splenic enlargement and blood changes are much in evidence, a diagnosis of primary splenic neutropenia is sometimes made. The results of splenectomy are variable. Usually there is an improvement in the blood picture with increased neutrophils, but this improvement is not maintained. However, the liability to infections seems to be decreased in many cases and rheuma­toid arthritis that has become resistant to steroid therapy may, once again, react favourably to the administration of steroids.

Tuberculosis

Tuberculosis of the spleen is not so uncommon as is some­times believed. It occurs chiefly in adults between 20 and 40 years of age. When a patient has splenomegaly with asthenia, loss of weight and an evening fever, it is well to bear in mind the possibility that the enlargement of the spleen may be due to tuberculosis. Too often the signs lead to erroneous diagnosis of leukaemia or some other disorder for which splenectomy is not indicated. Occasionally tuber­culosis of the spleen produces portal hypertension. Another form is cold abscess, which is very rare. Splenic puncture followed by culture or guinea-pig inoculation will yield positive results. A therapeutic test with antituberculous drugs (Chapter 8) brings about some improvement, and there is less danger of dissemination of the tubercle bacilli if splenectomy is undertaken. The operation, which is usually rendered difficult because of adhesions, is contraindicated only if other active tuberculous lesions are found to be present. Other­wise, the results of splenectomy in the treatment of tuberculosis of the spleen are excellent.

Neoplasms

The most common benign tumour of the spleen is the hae­mangioma which may, on occasion, develop into a haemangiosarcoma. Splenectomy may be necessary. The commonest cause of neoplastic enlargement of the spleen is lymphoma. Splenectomy may play a part in the management of these conditions (Chapter 17), but the role is now limited.

Porphyria

Porphyria is a hereditary error of catabolism of haemoglobin in which porphyrinuria occurs. The abdominal crises, which are characterised by violent intestinal colic with constipation, are liable to be precipitated by the administration of barbiturates, for which these patients have an idiosyncrasy. The patient is anaemic, frequently suffers from photosensitivity and, in advanced stages of the disease, neurological or mental symptoms (from damage to the brain) are commonly present. On examination, the spleen will be found to be enlarged. On a number of occasions the splenic enlargement, which is usually well marked, has been overlooked and the abdomen has been opened on the presumptive diagnosis of intestinal or appendicular colic, with negative findings. Another manifestation of acute porphyria is spasmodic abdominal pain followed by jaundice.

Two methods of establishing the diagnosis are available.

  The urine is sometimes normal in colour usually it is orange (often dismissed as ‘concentrated’). If a urine

specimen is left exposed to daylight for a few hours it develops a port wine colour, particularly near the surface where it is exposed to the air. There are several conclusive laboratory tests for porphyrinuria.

      Radiography of the abdomen serial radiographs show areas of intestinal spasm causing short segments of gaseous dilatation of the small and large intestine, and especially of the caecum.

Treatment

Often there is a striking decrease in the serum sodium level and the patient is improved considerably by the infusion of isotonic saline solution with careful control of electrolyte balance. Methadone is the best drug to relieve the abdominal pain. If a sedative is required, one of the phenothiazines (e.g. chlorpromazine) should be given. Splenectomy is not of value except in the uncommon erythropoeitic type with splenomegaly.

Gaucher’s disease

As mentioned, the spleen may take an active part in the storage of abnormal lipoids, as does the remainder of the reticuloendothelial system. In the case of Gaucher’s disease the lipoid in question is glucocerebroside. Gaucher’s disease, which is rare, is characterised by enormous enlargement of the spleen, which may weigh 8 or 9 lbs (3.6—4.1 kg). In most cases the splenic enlargement begins in early childhood, often before the age of 12 years, although the patient rarely seeks advice before adult life. Until the splenic enlargement becomes massive the symptoms are few. There is anaemia, a yellowish-brown discoloration of the skin of the hands and face, and a curious conjunctival thickening (pinguecula) that helps to clinch the clinical diagnosis. Slavonic and Jewish races appear to be more prone to the disease than other races. The diagnosis is confirmed by finding Gaucher’s cells in the bone marrow.

Treatment

Splenectomy rids the patient of a large abdominal swelling, but the operation is difficult because of perisplenitis and friability of the splenic pulp. It does not greatly influence the course of the disease, but because it reduces the hyper­splenism (anaemia, leucopenia and thrombocytopenia) and makes the patient more comfortable, the procedure may be indicated.

Leukaemia

Leukaemia is one of the conditions to be considered in the differential diagnosis of splenomegaly. The diagnosis can be made by examination of a blood or marrow film. The main treatment is chemotherapy or radiotherapy; occasionally marrow transplantation may be necessary. Splenectomy during the chronic phase of chronic granulocytic leukaemia will not reduce the incidence of blastic transformation or improve survival. The procedure should be reserved for hypersplenism occurring during the chronic phase, or for when bone marrow transplantation might be necessary. In rare instances the removal of a symptomatic enlarged spleen during the blastic phase produces relief, but the period of relief is brief and the operation hazardous.

Splenectomy is occasionally indicated for palliation of a painful bulky spleen in chronic lymphocytic leukaemia, but only after consultation with an experienced haematologist.

Abscess of the spleen

If a splenic embolus is infected, and the primary condition does not prove fatal, a splenic abscess may be expected to follow Other sources of metastatic abscess of the spleen are typhoid and paratyphoid fever, osteomyelitis, otitis media and puerperal sepsis. An abscess in the right upper pole of the spleen may rupture and form a left subdiaphragmatic abscess. If the abscess is in the lower pole, rupture results in diffuse peritonitis.

Treatment

As a rule, owing to dense adhesions, drainage of the abscess is the only course. Very rarely, splenectomy may be possible with the abscess in situ. The drainage may be performed percutaneously, under ultrasonic or CT guidance, so avoiding the need for operative intervention.