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RESEARCH ARTICLE
SA JOURNAL OF DIABETES & VASCULAR DISEASE
6
VOLUME 15 NUMBER 1 • JULY 2018
(58%) in this study were under this age. The relatively young age
of people developing limb ulcer(s) may have economic implications
in any economy. Also, complications generally ascribed to older age
groups are frequently being encountered in younger patients with
diabetes, contributing to early mortality.
6
There were more patients from the urban areas than from rural
areas but the relationship was not statistically significantly different
(
p
> 0.05). Type 2 diabetes is closely associated with (rapid)
urbanisation, westernisation, sedentary lifestyle and obesity.
1,6,7
These are common descriptive terms applicable to most urban
locale with many a rural area threatening to catch up.
1,8
Both civil and public servants are known to farm extensively
in Benue State, where this health institution was located. In the
peasant agrarian setting that most of these patients were drawn
from, poverty, inadequate footwear, increased risk of physical
trauma, infection during farming activities and spontaneous blisters
in bare-foot peasants and farmers were quite common.
7,8
Farmers constituted more than half of those presenting with
foot ulcers in this study. In addition, a situation where almost 60%
of participants had primary or no Western education, widespread
ignorance about appropriate health promotive and preventative
activities would be expected. The higher the educational level,
the lower the incidence of foot ulcers.
8
Other researchers have
observed an even higher level of poor Western literacy rate among
their respondents. Akanji
et al
. observed that up to 68% of their
sample in a prospective study was without Western education.
9
A number of research bodies on foot ulcers in people living
with diabetes from the developing world feature late presentation
to hospital as a common threat.
8,10,11
Up to 72.5% of patients in
this study sought medical attention after three months of home/
alternative/unorthodox treatment, for several reasons, including
ignorance, fear of orthodox medical practices and inadequate
transport.
10,11
This problem is still begging for a solution.
10
Sadly,
many of the reasons were eminently solvable through education of
individuals living with DM and their (primary) health providers.
12,13
Generally, the patients in this study had poor glycaemic control,
as evidenced by HbA
1c
levels > 6.5%, which occurred in 78% of
patients in this study. The Diabetes Control and Complications Trial
(DCCT) research groupwere able to demonstrate a direct relationship
between poor glycaemic control and microvascular complication.
14
Also, the United Kingdom Prospective Diabetes Study (UKPDS)
clearly showed that each percentage point reduction in A
1c
was
associated with a 35% reduction in microvascular complications,
such as neuropathy, a cardinal cause of foot disease in people living
with diabetes.
15
Other researchers have also noted varying degrees of poor
glycaemic control in their subjects, especially using casual and
fasting plasma glucose estimations.
14-17
However, comparisons are
rather difficult due to lack of uniformity in testing. Some researchers
have determined HbA
1c
level, while others have used random or
fasting plasma glucose assessments due to cost, convenience or
unavailability of HbA
1c
tests.
14,16,17
Because of prolonged exposure of tissue proteins to glycation
processes, the duration of diabetes mellitus is thought to be a
predisposing factor to diabetic complications in general, especially
in poorly controlled patients.
14,15
This is understandable in view of the
variably long latency in the natural history of diabetes mellitus from
the time of the initiating injury to clinical detection (as evidenced
by the development of hyperglycaemia), up to the development of
complications.
16
Wound infection is a common occurrence in diabetic ulcers.
5,18,19
This often leads to prolonged hospital admission
18,19
and increased
costs.
19
On the whole, Gram-negative bacilli were the predominant
organisms observed on Gram stain in this study, making up 50.9%of
all the bacteria. However, the Gram-positive coccus,
Staphyllococcus
aureus
, constituted the majority of individual isolates, at 31.2%.
This is in agreement with the findings from other publications that
demonstrated a preponderance of
S Aureus
.
20-23
S aureus
is a common skin commensal, harboured in the anterior
nares of nearly half of the global population and colonising the
armpits, perineum and the respiratory tract of countless others.
Coupled with the relatively reduced immune activity of people living
with diabetes mellitus,
S aureus
would become more ubiquitous,
invasive and virulent. However, this is not a universal finding, as
studies equally exist demonstrating the pre-eminence of a variety
of other bacteria.
6,19
Apart from a mono-microbial pattern, other researchers have
been able to culture more than one organism from an ulcer.
Indeed, poly-microbial culture is quite common.
5,9,18,19,21
In this study,
a combination of staphylocci and coliforms were cultured from only
four ulcers out of the 109 studied.
Many factors could explain the ‘no growth’ observed in three
cultures. While it could be true that the ulcers were indeed sterile,
poor swab technique, wrong storage conditions, long ‘wait’ interval
between collection and inoculation in the laboratory, wrong growth
media/conditions, strict aerobes and anaerobes, and inappropriate
antibiotic use should be borne in mind as possible factors in
interpreting and making decisions on this observation. It would be
better to err on the side of caution, judging from the history, local
findings around and on the ulcer, and systemic examinations in
evaluating this type of occurrence.
One of the ‘no growth’ swab samples, whichwas finally identified
as a fungus, was further characterised to be yeast. Undiagnosed
and with inappropriate anti-infective drugs, this ulcer may not heal.
The time-tested teaching emphasising the need for further efforts
in carrying out cultures of samples from refractory ulcers to ensure
fungal colonisation (especially yeast) should be borne in mind,
especially in resource-constrained areas.
18
Two important observations stand out on antibiotic susceptibility
testing: the high degree of resistance to penicillins (especially
Ampicillin) and the relatively high rate of sensitivity to quinolones.
The cephalosporins were seldom effective and unless suggested from
antimicrobial susceptibility testing, these drugs should not be used as
initial therapy for diabetic foot infections in our environment.
19
The resistance to antibiotics of many of these microbes is
not surprising because of drug misuse, which is widespread in
sub-Saharan Africa. It is not uncommon to observe antibiotics
being marketed in commercial vehicle parks, open markets and
supermarkets by unlicensed vendors. Some of the strains of
bacterial isolates that colonised the refractory diabetic ulcers in
this study may have acquired genes for drug resistance through
antibiotic misuse.
5
Quinolones were therefore recommended as the
initial therapy for people living in this environment with diabetes
with infected ulcers while awaiting culture results, which should be
used to guide further antibiotic therapy.
Limitations
Bacterial culture results were a very important component of this
study. The observed results may have been different if certain factors
affecting the patient and/or their investigations were different. For