Condition category
Infections and Infestations
Date applied
Date assigned
Last edited
Retrospectively registered
Overall trial status
Recruitment status
No longer recruiting

Plain English Summary

Not provided at time of registration

Trial website

Contact information



Primary contact

Mrs Marianne Emilie Visser


Contact details

PO Box 6614
Cape Town
South Africa

Additional identifiers

EudraCT number number

Protocol/serial number


Study information

Scientific title

The effect of vitamin A and zinc supplementation on the bacteriological response of persons with pulmonary tuberculosis in the Western Cape


Study hypothesis

To investigate the efficacy of vitamin A and zinc supplementation for 2 months, in conjunction with standard anti-tuberculous therapy, on the bacteriological response of adults with newly diagnosed smear-positive pulmonary tuberculosis.

In South-Africa tuberculosis accounts for more than 80% of all communicable diseases and is regarded as one of the most serious health problems affecting the country. There are an estimated 556 cases per population of 100,000 each year, with the highest incidence in the Western Cape. HIV infection is the greatest individual risk factor for tuberculosis and more than half of smear-positive patients are HIV-infected in South Africa. A recent Indonesian study investigated the combined effect of vitamin A and zinc supplementation to adults with pulmonary tuberculosis. Conversion of positive sputum smears was significantly faster in the micronutrient group than in the placebo group after 2 months of anti-tuberculosis treatment. Earlier sputum conversion is critical in terms of tuberculosis control in South Africa. Our study will therefore aim to determine the efficacy of a low cost micronutrient intervention on short-term outcomes such as bacteriological and immunological responses as well as clinical and nutritional parameters in smear positive adult pulmonary TB patients within the context of co-infection with HIV.

Ethics approval

Research and Ethics Committee at the University of Cape Town, 08/03/2005, ref: REC 137/2003

Study design

Randomized double-blind placebo-controlled trial

Primary study design


Secondary study design

Randomised controlled trial

Trial setting

Not specified

Trial type


Patient information sheet


Pulmonary tuberculosis


Patients will be randomly assigned to the following two groups:

Intervention group: A single dose of 200 000 IU vitamin A (capsule, orally) at study entry plus daily supplementation of 15 mg zinc (tablet, orally) for 2 months
Control group: Placebo capsules (orally) at study entry plus daily placebo tablets (orally) for 2 months.

Both groups will receive standard anti-tuberculosis treatment in addition to the supplement or placebo.

Intervention type



Not Specified

Drug names

vitamin A and zinc

Primary outcome measures

Sputum smear and culture conversion rates, measured every week up to 8 weeks.

Secondary outcome measures

The following will be assessed at baseline, 2 and 8 weeks:
1. Radiologic resolution
2. Anthropometrical status (body mass index, arm muscle circumference, percentage body fat)
3. Serum micronutrient levels (retinol, zinc, iron and copper)
4. Performance status (Karnofsky scale)
5. Immunological parameters (Interferon-gamma)

Overall trial start date


Overall trial end date


Reason abandoned


Participant inclusion criteria

Patients with newly diagnosed smear-positive pulmonary tuberculosis attending community health care centres in Delft, Cape Town.

Participant type


Age group

Not Specified


Not Specified

Target number of participants


Participant exclusion criteria

1. Re-treatment patients
2. Patients with extra-pulmonary tuberculosis
3. Patients with Multi-Drug Resistance (MDR) at baseline or during follow-up
4. Patients with elevated alanine transaminase levels (>5 fold increase)
5. Women who are pregnant or wish to become pregnant
6. Women who have given birth within 6 months of study entry
7. Patients with clinical signs of liver disease, renal failure, congestive heart failure or neoplasm 8. Use of corticosteroids
9. Use of supplements containing vitamin A, zinc or iron during the previous month prior to treatment
10. No consent given for a voluntary HIV-test at baseline

Recruitment start date


Recruitment end date



Countries of recruitment

South Africa

Trial participating centre

PO Box 6614
Cape Town
South Africa

Sponsor information


University of the Western Cape, School of Public Health, Division of Dietetics (South Africa)

Sponsor details

Division of Dietetics
School of Public Health
University of the Western Cape
Private Bag X17
Cape Town
South Africa

Sponsor type




Funder type

Not defined

Funder name

National Research Foundation, South Africa Institutional Research Development (grant number: 2067444)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Funder name

The Norwegian Programme for Development, Research and Higher Education Network (grant number: NUFUPRO-2007/10183)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Funder name

South African Sugar Association Nutrition Research (grant number: 200)

Alternative name(s)

Funding Body Type

Funding Body Subtype


Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

2011 results in:
2015 results in:

Publication citations

  1. Results

    Visser ME, Grewal HM, Swart EC, Dhansay MA, Walzl G, Swanevelder S, Lombard C, Maartens G, The effect of vitamin A and zinc supplementation on treatment outcomes in pulmonary tuberculosis: a randomized controlled trial., Am. J. Clin. Nutr., 2011, 93, 1, 93-100, doi: 10.3945/ajcn.110.001784.

  2. Results

    Chigutsa E, Pasipanodya JG, Visser ME, van Helden PD, Smith PJ, Sirgel FA, Gumbo T, McIlleron H, Impact of nonlinear interactions of pharmacokinetics and MICs on sputum bacillary kill rates as a marker of sterilizing effect in tuberculosis, Antimicrob Agents Chemother, 2015, 59, 1, 38-45, doi: 10.1128/AAC.03931-14.

Additional files

Editorial Notes