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The incidence of malaria after splenectomy in Papua New Guinea

BMJ 1995; 311 doi: http://dx.doi.org/10.1136/bmj.311.7015.1273 (Published 11 November 1995) Cite this as: BMJ 1995;311:1273
  1. Ken E Boone, surgical specialista,
  2. David A K Watters, professora
  1. aDivision of Surgery, PO Box 5623, Boroko, Papua New Guinea
  1. Correspondence to: Professor Watters.Department of Medical Statistics, Research and Teaching Building, University Hospital of South Manchester, Manchester M20 8LR Julie Morris, senior medical statistician.
  • Accepted 20 August 1995

In the tropics, as in the developed world, the spleen is the commonest intra-abdominal organ to be injured.1 2 Splenic enlargement due to chronic malaria predisposes to splenic injury, particularly in low velocity blunt trauma due to domestic violence or assault, both of which are common in Papua New Guinea. In developed countries the risk of sepsis after splenectomy has resulted in a more conservative approach to splenic trauma.3 4 In the tropics death from malaria after splenectomy has been reported, but no formal study has been undertaken.2 5 We studied the sequelae of splenic trauma and splenectomy in patients living in an area of Papua New Guinea where malaria is endemic.

Patients, methods, and results

The study was performed in East New Britain in the Bismarck Archipelago. Nonga Base Hospital, Rabaul, is the islands' referral hospital, and the plantations employ people from all over Papua New Guinea. In 1982-92, 115 patients were treated for splenic trauma, 31 by splenectomy and 84 by splenic conservation. Despite considerable effort, only 56 patients were traceable in 1993, largely because the others had moved to remote parts of Papua New Guinea (35 had returned to the Highlands, a non-malarious area). Six of the 56 had died; the causes of death could not be verified in the two who had undergone splenectomy, while relatives stated old age, bomb blast, cancer, and sorcery as causes in the four with conserved spleens. This left 50 patients (17 who had undergone splenectomy and 33 splenic conservation) who were followed up to obtain a history of post-trauma illnesses (malaria, upper respiratory tract infection, sores, influenza, tuberculosis) and to take blood for a full blood count and malarial film. We also studied 50 controls, similar in age, sex, and place of origin to the patients and admitted to the surgical wards during the same period for a non-traumatic cause. Data were analysed using the χ2 test.

All 17 patients who underwent splenectomy reported that they had had malaria compared with only 18 of 33 (55%) in the conservation group and 23 of 50 controls (P<0.05). Upper respiratory tract infections were also more common in the splenectomy group (table). Fifteen (88%) of the splenectomy group were positive for malaria at the time of interview compared with six (18%) of the conservation group and eight (16%) controls (P<0.001). The patients who had undergone splenectomy also tended to have a higher leucocyte count (P<0.01), but there was no difference in haemoglobin concentrations. Compliance with antimalarial prophylaxis declined from 100% in the first year to 29% after three years in the splenectomy group.

Illnesses and results of blood examination in patients with splenic trauma and hospital controls 1-10 years after injury. Values are numbers (percentages) unless stated otherwise

View this table:

Comment

We could follow up only 56 of 115 patients with splenic trauma, but the results still suggest a high incidence of malaria in patients who had undergone splenectomy. All these patients reported having malaria, and although the history given may be unreliable, the fact that 88% were also carrying malaria parasites is convincing evidence that malaria is a major risk after splenectomy. Our data do not suggest that post-splenectomy malaria caused death, but others have reported death from malaria after splenectomy.2

In Papua New Guinea splenic conservation has been practised for over a decade, and the splenectomy rate in splenic trauma has been reduced to below 30%.2 When splenectomy is performed every effort should be made to ensure that patients living in endemic areas continue to take anti-malarial prophylaxis for life in addition to pneumococcal vaccination and penicillin prophylaxis. Those living in the tropics, but outside malarious areas (above 5000 feet), require prophylaxis when they travel into an endemic zone.

Footnotes

  • Funding None.

  • Conflict of interest None.

References