Laparoscopic Subtotal Splenectomy in Children and Adolescents With Spherocytosis

Removal of the spleen in hereditary spherocytosis can contribute to normalizing hemoglobin and the reticulocyte count by reducing hemolysis (1). By preserving a small part of the spleen the immunological and phagocytic functions of the spleen can be retained. Subtotal splenectomy is, however, a more complex procedure than total splenectomy, and there is no unequivocal evidence supporting it, so that the indication for partial resection is defined only with hesitation to date.

Methods

We carried out a retrospective analysis of data from all children (0–17 years old) in whom laparoscopic subtotal splenectomy was undertaken for spherocytosis at the department for pediatric surgery at University Medical Center Hamburg-Eppendorf between 2016 and 2019. The patients were identified on the basis of ICD-10 codes. We evaluated the parameters age, sex, spleen volume, hemoglobin and thrombocyte counts, perioperative complications, and length of inpatient stay. The splenic volume was reduced by about two-thirds, preserving about 10% of the superior pole of the spleen. For vascular ligatures and transections, 10 mm PDS clips or LigaSure were used.

Standard follow-up consisted of repeat examinations after three and six months. The full blood count was checked, abdominal sonography was carried out, and pitted erythrocyte testing was undertaken.

Queries with the Federal Statistical Office

Furthermore we ran queries through the German Research Foundation database at the Federal Statistical Office for the years 2016 and 2017 based on ICD-codes (M31, D47, D56, D57, D58, D59, D69) und OPS codes (5–4130, 5–41301, 5–41300, 5–4131) [OPS, the Operationen- und Prozedurenschlüssel, is the German modification of the International Classification of Procedures in Medicine].

Results

In four years, 16 children at our center met our inclusion criteria. The mean follow-up period was 34.6 (SD, 10.3) months. The children’s mean age was 12.4 (SD, 3.5) years. Moderately severe spherocytosis was seen in 11 of 16 cases, severe spherocytosis in three cases, and very severe spherocytosis in two cases. The classification was done on the basis of hemoglobin, reticulocyte, and bilirubin counts and data from the peripheral blood film and a possible need for a transfusion. 11 of 16 patients received at least one transfusion of packed red blood cells preoperatively. The mean duration of the operation was 219.4 (SD, 92.8) minutes; in four children cholecystectomy for confirmed gallstones was undertaken during the same procedure. As Figure a shows, this was a learning curve for the entire center. One operating surgeon was involved in almost all operations (15/16). The mean length of the inpatient stay was 5.7 (SD, 2.3) days. No relevant intraoperative complications were observed. Conversion to an open procedure was not required in any of the children. In five out of 16 cases, a predominantly left-sided pleural effusion developed postoperatively, which resolved spontaneously. None of the patients experienced impaired wound healing or contracted a wound infection. Reoperation was not required in any of the cases.

Transient thrombocytosis with a peak after about 12 weeks was observed (Figure b), with thrombocyte aggregation inhibited in four of 16 children. None of the patients presented within the follow-up period with renewed increase in spleen volume in the sense of splenic rebound. A rise in and stabilization of hemoglobin counts occurred within a few weeks. Hemolysis was not observed in any of the patients postoperatively. One child tested positive for pitted erythrocytes after three months. After six months, findings in all children were normal, with values <3% (2).

Figure.

a) The duration of the surgery shortens significantly over time (p = 0.02). At the end subtotal splenectomy including cholecystectomy took less than two hours.

b) Subtotal splenectomy induces pronounced thrombocytosis in all children, which peaks after 12 weeks and normalizes completely and in a sustained manner after very few months.

National comparison

In Germany in 2016 and 2017, a total of 109 children underwent splenectomy for a hematological disorder. Of these, 71 cases were subtotal splenectomies, and 55 of these were done laparoscopically. Germany apparently has a maximum of three centers that carry out more than nine laparoscopic subtotal splenectomies in children within two years.

Discussion

In all 16 children, a subtotal splenectomy was successfully done laparoscopically. The most common postoperative complication consisted of mild pleural effusion with spontaneous regression over time. In the current study, the duration of the procedure was reduced from initially more than three hours to less than two hours. In principle it has been described that the result of surgically demanding procedures, such as oncosurgery, yields significantly better results in so called high volume centers (>25 cases per year) than in hospitals with lower case numbers (3). Consequently it seems sensible to undertake subtotal splenectomies in high volume centers.

The postoperative counts of pitted erythrocytes provide confirmation that very good spleen function has been retained. This is also reflected in the merely transient thrombocytosis. Within the follow-up period of at least 18 months, spleen volume remained stable, without rebound tenderness. Children in the current study were notably older (median >12 years) than in earlier studies with a median age of 6 years, in which 25% had to be re-operated because of spleen rebound (4, 5). The results imply that with increasing age the effect of spleen rebound recedes and that the timing of the operation should be chosen accordingly. The normal hemoglobin range for a mean age of 12 years was reached by all patients in the follow-up period. Postoperative transfusion owing to hemolysis was not needed in any of the children during the subsequent follow-up period. Of note, the observation period was short. Some effects, such as spleen rebound, might develop only over time.

Conclusion

The results of our study suggest that laparoscopic subtotal splenectomy possibly constitutes a safe and effective alternative to total splenectomy. Further systematic analyses are required to validate the benefits of partial splenectomy in children and adolescents with hereditary spherocytosis.