Hi thank you for your question. Please remember to RATE my answer OK SERVICE, GOOD SERVICE OR EXCELLENT SERVICE so I can get credited for my time.
No, this should not be the case as terminal illness such as HIV can not be the basis for refusal unless other factors are taken into account. Please see below the internal guidance issued by the UKBA regarding applications with terminal illness:
If an applicant for entry clearance has a serious illness, for example HIV / AIDS, the Entry Clearance Officer (ECO) should decide on the application under the provisions of the Rules or, if in doubt, refer it to:
Entry Clearance referrals, RCU, UK Border Agency, through the Home Office referrals mailbox. Supporting material should be scanned and sent by email. For further information see section on Referrals.
The fact that an applicant has a serious illness is not sufficient grounds in itself for ECOs to exercise discretion in issuing an entry clearance. Where in any case it appears that public health may be at risk, advice should be sought from the Department of Health. You may want to contact the Public Health Unit for further information.
Department of Health
Aspects of Public Health Unit
80 London Road
Tel: +4420 7972-2000
Fax: +4420 7972-5138
The ECO must refer all such persons to the Medical Officer for a medical examination.
The Medical Referee's recommendation should contain a recommendation as to whether the applicant is able to maintain himself / herself and, if relevant, any dependants, during his / her stay in the UK. For instance, although a person who is HIV positive may be well enough to work, study or undertake a visit, a person with full blown AIDS may not be capable.
If an applicant appears to be so ill that it is likely that he / she would require medical treatment while in the UK and the person could not meet the cost of the treatment privately, the ECO should consider refusal under the general provisions of the Rules. Paragraph 37 of the Rules covers those who suffer from a disease or condition which would prevent them from supporting themselves or their dependants.
If the ECO believes that the applicant intends to travel to the UK as a visitor in order to obtain free medical treatment, the ECO may refuse entry because he/she is not satisfied that the applicant is genuinely seeking entry as a visitor (paragraph 41(i)).
Visitors to the UK are not entitled to receive free (non- emergency) National Health Service hospital treatment on a visit to the UK unless they are considered exempt from charge under the NHS (Charges to Overseas Visitors) Regulations 1989, as amended (see guidance in the Visits section).
More information is available on the Department of Health - Information for overseas visitors
Depending on your current condition and how ill you currently are will be factors taken into account by the UKBA, they will also look into in medical treatment is needed will you or your partner be able to pay for such treatment as free treatment will not be available to you until you have obtained an indefinite leave to remain status in the UK.
I hope this answers your question, if so kindly rate my answer positively so I can get credited for my time.