Cardiovascular Journal of Africa: Vol 28 No 4 (July/August 2017)

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CARDIOVASCULAR JOURNAL OF AFRICA • Volume 28, No 4, July/August 2017 AFRICA 221
The prevalence and radiological findings of pulmonary
embolism in HIV-positive patients referred for computed
tomography pulmonary angiography in the Western
Cape of South Africa
Raksha Ramlakhan, Savvas Andronikou, Ashmitha Rajkumar
Abstract
Aim: To provide imaging data and report associations between
human immunodeficiency virus (HIV), tuberculosis (TB) and
pulmonary embolism (PE) in a South African population that
underwent computed tomography pulmonary angiography
(CTPA) for suspected PE.
Methods: A validated Qanadli severity scoring system for
PE was used for 164 CTPA scans, and parenchymal, pleural
and cardiovascular complications were reported. Serological
confirmation of HIV testing and microbiological confirma-
tion of TB were recorded.
Results: Prevalence of PE in the CTPA population was 26%
(95% CI: 19.67–33.65%). HIV-positive prevalence in patients
with PE was 67% (95% CI: 48.17–82.04%), however it was
not statistically significantly different when compared with
the patients without PE (p = 1). HIV-positive patients had
more extensive partial thrombus in the right middle lobe
( p = 0.045), but no other differences when compared with
HIV-negative patients. TB prevalence in patients with PE was
57% (95% CI: 34.49–76.81%). This was statistically signifi-
cantly different when compared with the patients without PE
( p = 0.073 at the 10% level). Prevalence of TB co-morbidity
in the HIV-positive group with proven PE was 71% (95% CI:
41.90– 91.61%), however there was no statistically significant
difference in comparison with the HIV-negative patients with
TB and PE (p= 0.305).
Conclusion: The high number of patients presenting for
CTPA who were HIV infected (and also infected with TB)
highlights that PE evaluation should include severity/extent
of the disease, as these patients may have more severe disease
in specific lung lobes. The use of a validated scoring system,
such as the Qanadli score, when reporting PE may have a
profound effect on patient risk stratification, management
and prognosis and would also provide a system for collecting
larger volumes of data for analysis.
Keywords: pulmonary embolism, computed tomography pulmo-
nary angiography (CTPA), HIV, Western Cape
Submitted 5/6/16, accepted 21/9/16
Published online 15/2/17
Cardiovasc J Afr 2017; 28: 221–228
DOI: 10.5830/CVJA-2016-083
Pulmonary embolism (PE) is a life-threatening condition if not
diagnosed early. The overall mortality rate in untreated patients
is 30%, with approximately 10% of patients dying within one
hour of the event.1 Haemodynamically unstable patients have
the highest mortality rate, which can be as high as 58%.1 In the
United States, PE is the third leading cause of death, accounting
for 100 000 to 300 000 estimated deaths per year.2 In Europe, an
estimated 370 000 PE-related deaths occur annually.3
In Africa, PE has been reported in 3.8% of autopsied
patients in Nigeria.4 Ogengo et al. described a PE incidence
rate of 0.032% over a five-year period in black Africans at a
tertiary hospital in Kenya.5 A study undertaken at a university-
affiliated hospital in Cameroon reported a 32.4% incidence of
PE in patients with clinical suspicion of PE, using computed
tomography pulmonary angiography (CTPA).6
In an autopsy series conducted in an adult population in Cape
Town between 2001 and 2005, pulmonary thromboembolism
was found to be the third most common cause of natural death
in females.7 The true prevalence of PE in South Africa however,
remains largely unknown.
Human immunodeficiency virus (HIV) is a hypercoagulable
state that predisposes patients to a two- to 10-fold increased
risk of venous thromboembolic events, such as pulmonary
emboli, in comparison with the general population.8 Venous
thromboembolic disease (VTE) in association with HIV has
been reported in the literature since 1980.9 In 2011, a systematic
review by Bibas et al. looked at 13 main studies on VTE, from
1991 to 2007, which reported on the occurrence of VTE among
HIV-infected patients, with a frequency ranging from 0.19 to
7.63% per year.8 In Africa, HIV in association with PE was
reported as a co-morbidity occurring in 10.9% of hospitalised
black Kenyan patients.5 The prevalence of HIV in association
with PE in South Africa is not known.
The work undertaken on VTE in TB-infected patients in
Africa is limited. A Kenyan study by Ogengo et al. reported that
TB was present as a co-morbid condition in 12.5% of hospitalised
Department of Radiology, Groote Schuur Hospital and
University of Cape Town, South Africa
Raksha Ramlakhan, BMedSc (UDW), MB BCh (Wits),
Department of Paediatric Radiology, University of Bristol
and the Bristol Royal Hospital for Children, Bristol, United
Kingdom and Department of Radiology, University of Cape
Town, South Africa
Savvas Andronikou, MB BCh (Wits), FCRad (Diag) (SA), FRCR
(Lond), PhD (UCT), PhD (Wits)
Department of Radiology, Mitchell’s Plain Hospital,
Mitchells Plain, Cape Town, South Africa
Ashmitha Rajkumar, MB ChB (UCT), FCRad (D) SA