Leukamia in Kenya
Abstract
The main objective of the study was to show that leukaemia
was more common in Kenyan Africans than has been the belief
from impressions. Literature review revealed that there
ave been sporadic case reports of leukaemia in Kenyan
Africans since 1924. However, increasing leukaemia
documentation has only featured in the seventies because
f the progressively developing awareness and interest in
the disease (Table 3, page 20).
This retrospective and prospective study covered 456 cases
of all types of leukaemia diagnosed at the Kenyatta National
Hospital between 1971 and 1977. Those cases admitted to this
hospital were further fully investigated and treated if they
did not die immediately. Then several clinicopathological
variables and biodata were analysed in all the cases.
The overall n at.LonaL crude incidence is 0.5 cases per
100,000, with a maximum tribe-specific incidence being
1.2 cases per 100,000. Childhood (below 15 age group)
leukaemia accounted for 28% of all types of leukaemia, giving
an incidence of 0.3 cases per 100,000, in contrast to the
adult incidence of 0.7 cases per 100,000. However, 48% of
all acute leukaemias occurred in childhood as compared with
only 4.7% of the chronic types. There is a peak occurrence
of all types of leukaemia in the first decade of life, with
a minor secondary peak in the sixth decade. The nadir
appears in the 4th and 5th decades. There is an apparent
deficit of acute lymphocytic leukaemia in the 0-4 year age group
but acute myclogenous presents with a peak in the
second decade of life. Chronic granulocytic has tl1e highest
prevalence in the 20-40 year age-group and chronic lymphocytic
in the 40-70 year period. There is an overall male to
female ratio of 1.47:1, but the childhood ratio is 1.7:1.
Tribal distribution correlates with proximity of various
tribes to medical services and there is no obvious
geographical pattern.
Leukaemia typing shows that the myeloid leukaemias are
twice as frequent as the lymphocytic types, with the
following distribution: AML (including myclomonocytic) -
31.6%; ALL (including acute prolymphocytic) -14.9%;
ALSCL - 5.5%; AMoL - 3.3%; AUL - 0.9%; CGL - 28.5%;
LL - 15.3%; ALSCL emerges as an important entity, which
occurs maximally in the 5-9 year age~group.
I The general behaviour of leukaemia sho1\1sno gross
difference from what is known about leukaemia from elsewhere.
However, subtle but important features stand out.
The majority of patients present with advanced disease,
most often in terminal stages, as is evidenced by the high
mortality rate within the first month after diagnosis,
frequent gross organomegaly, severe anaemia and thrombocytopenia,
hyperleucocytosis (37% over 200xl09/l; 42% over
30xl09/1,) or marked blastaemia with the generally poor
clinical performance. There is a high frequency (23%)
of facial chloromatous presentation in childhood AML
and AM-ML, which often simulate Burkittc's lymphoma.
Cases of acute leukaemia masquerading as rheumatoid
arthritis or aplastic anaemia are not uncommon.
There were remission induction rates of 69% for all
the acute leukaemias, in which ALL had 85% and AML - 54%.
None of the patients with AMoL or AUL attained remission.
Sixty three percent of AML, patients died within one
mom.h and almost all were dead within 12 months after .-
diagnosis. Only 32% of ALL patients died within one month,
and 37% survived for more than 12 months (Fig. 20). In
childhood acute leukaemia, about 90% of ALL attained. remission
status, only 10% died within one month and all had a
median survival of 15 months. Similarly.>60% of children
with AML went in to remission and all had a median survival
of only 8 months. The chronic leukaernias showed orthodox
features although CLL appeared to have a poorer outlook than CGL
(Fig. 20).
The quality of survival, even if reasonable, was
interrupted by a diversity of infections which often
caused death. Autopsy in 76 cases confirmed that death
was due to haemorrhage in 24%; infection - 20%; multiple
causes - 16%; other causes, including organ failure -
30%. No disseminated fungal infection was encountered.
The problems of diagnosis with consequent underdiagnosis
of leukaemia in Kenya are highlighted. Effective
management of this disease,in Kenya, is beset with
problems of ignorance by the public, patients, as well as
the lack of medical team work and the prohibitive socioeconomic
factors.
Thus, leukaemia is a common disease in Kenya, as it
also accounts for 4% of medical and paediatric admissions.
Its behaviour is, in general, the same as is known about
it elsewhere , although it appears to be more aggressive,
probably due to the late presentation of patients. There
is urgent need for establishing its precise incidence by
comnunity surveys and also a thorough study of
associated aetiological factors. For the present, acute
awareness of its existence is mandatory if early diagnosis,
which is a prerequisite to successful management, has to
be made.
Citation
Doctor of MedicinePublisher
University of Nairobi