Case Report: A 22-year-old male presented with complaints of high grade fever of one week's duration and pain in the left hypochondrium for two weeks. The pain had worsened in the last two days. Examination revealed the patient to be pale and hypotensive (systolic BP - 70mmHg) with splenomegaly and tenderness in the left hypochondrium. The Hb was 5g% and the BUN and creatinine levels were raised.

RADIOLOGICAL FINDINGS:

A plain CT Scan of the abdomen showed massive splenomegaly with subcapsular hematoma with ascites.

Repeated blood transfusions were carried out, but they failed to correct the anemia and hypotension. Finally, an exploratory laparotomy was considered. Thus, splenectomy was done 48 hrs after admission.

Histopathology showed Infectious Mononucleosis to be the cause of splenomegaly.

The patient recovered completely, and was discharged on the 8th day without any sequele.

DISCUSSION:

Splenic rupture as a result of blunt abdominal trauma is common. Rupture of the spleen without any history of trauma may occur occasionally. Atraumatic splenic rupture is an uncommon and potentially fatal clinical entity. In such a cases, the spleen may either be normal or may have some underlying pathology in which case it is better called 'pathological rupture of spleen'.

Spontaneous rupture of the spleen is a potentially fatal condition and timely resuscitation with surgical intervention could be life saving. Hence, a high degree of suspicion by the clinician is required to successfully treat such patients.

A number of pathological conditions which can cause spontaneous splenic rupture have been recongnised and these are listed below.
Infectious causes
Infectious mononucleosis
Viral Hepatitis
Subacute bacterial endocarditis
Typhoid fever
Relapsing fever
Tuberculosis
Tularemia
Brucellosis
Syphilis
Malaria
Kalazar

Hematologic and Neoplastic causes

Hemophilia
Anticoagulation
Hemolytic anemia
Myeloid metaplasia/fibrosis
Lymphoma and leukemia
Multiple myeloma

Gastrointestinal causes

Crohn's disease
Pancreatitis

Infiltrative causes

Amyloidosis
Felty's syndrome
Gaucher's disease
Sarcoidosis
Metastatic cancer

Malaria is the commonest cause of spontaneous splenic rupture in the tropics, while in the Western world its infectious mononucleosis.

To diagnose a case as spontaneous rupture of normal spleen, following criteria must be fulfilled:

1. No history of trauma either prior to operation or retrospectively after operation.
2. No evidence of disease that can affect the spleen.
3. No evidence of perisplenic adhesions or scarring of the spleen, which suggests trauma or previous rupture.
4. The spleen should be normal on gross and histologic examination other than findings of hemorrhage and rupture.
5. Full virological studies of acute phase and convalescent sera should show no significant rise in viral antibody titers suggesting recent viral infection of types associated with splenic involvement. These include Epstein-Barr virus, cytomegalovirus, and hepatitis viruses.

The etiology of spontaneous rupture of the normal spleen is not known. There are many different speculations regarding the cause of this rare clinical entity, but most of these theories lack strong evidence to support them. These theories include:

1. Localized involvement of the spleen with a pathologic process, which, during rupture, destroys all evidence of pathology.
2. Reflex spasm of the splenic vein causing acute splenic congestion.
3. Portal venous congestion with chronic splenic congestion.
4. Abnormally mobile spleen that undergoes recurrent torsions with resultant congestion leading to rupture.
5. Rupture of a degenerative or aneurysmal splenic artery.
6. Forgotten or unnoticed trauma.
7. Sudden increase in abdominal pressure leads to rupture

The most common symptom in a case of spontaneous splenic rupture is upper abdominal pain, usually worse in the left upper quadrant. This pain is classically referred to the left shoulder (Kehr sign) and may be associated with nausea, vomiting, dizziness, or syncope. The physical findings are those of peritonitis and acute hemorrhage. Laboratory investigation may show a normal or low hemoglobin level. Plain radiographs of the abdomen may reveal splenic enlargement with a resultant impression on the stomach and inferior displacement of the splenic flexure. The left hemidiaphragm is elevated with impaired motion. Small amounts of free fluid may be detected in the left paracolic gutter. However, none of these findings is pathognomonic - the more signs present simultaneously, the more likely the diagnosis.

The angiographic findings of splenic rupture include contrast extravasation, a "mottled" parenchymal phase, arteriovenous shunts with early venous filling and bowing, stretching, and crowding of vessels. Other less helpful signs are discontinuity of the splenic contour, displacement of the spleen from the lateral thoracic wall, and splenic artery spasm. CT has supplanted angiography as the preferred investigative modality, clearly showing a splenic hematoma or rupture.

Splenectomy, rather than conservative management, is considered the treatment of choice for these patients. It is curative, safe, and obviates the need for transfusion, extended hospitalization, and activity restriction.