Human Immune Deficiency Virus (HIV) infection is one of the most devastating infections in modern times. If untreated, almost all the patients with HIV infection will ultimately develop the dreaded Acquired Immunodeficiency Syndrome (AIDS).
AIDS is a disorder of the cell-mediated immunity, characterized by opportunistic infections, malignancies, neurological dysfunction and a variety of other infection. It is the most severe manifestation of a spectrum of HIV related conditions.
An estimated 40.3 million HIV infections and 10 million AIDS cases have been reported worldwide. The brunt of the disease is largely borne by communities in the sub Saharan Africa where an estimated 28 million people are living with HIV/AIDS. In Nigeria, there is a median prevalence of 5.0% HIV/AIDS cases spreading largely through unprotected sex in heterosexuals and as at December 2005, the estimated figure of people infected with HIV/AIDS in Nigeria was 3.8million. (UNAIDS/WHO)
Oral manifestations of HIV occur in approximately 30-80% of all affected patients, and the factors, which predispose to the expression of these lesions include; CD4 count (<200 cells/mm), viral load, xerostomia, poor oral hygiene and smoking.
These manifestations have been important entry criteria for clinical trials (and end point in these trials) as well as for vaccines studies.
The principal cellular target of HIV infection is the CD4 T-helper cells and the depletion of these cells is a central factor in the progression of HIV infection and AIDs as a disease.
This cellular immune dysfunction results in the inability of monocytes and macrophages to kill intracellular pathogens effectively so that various opportunistic pathogens can produce infection in such instances.
lIn Nigeria, the CD4 cell count in healthy individuals has been found to range from 636/mm3 to 977/mm3. However, in developed countries, the mean value of CD4 cell count in normal individuals ranges from 1000/mm3 to 1100/mm3. The relatively lower values in Nigeria and probably in other Africa countries may be due to the constant exposure of inhabitants in these countries to a large number of pathogens
A possible explanation for these oral lesions is probably related to the ever-present potentially pathogenic flora of the oral mucosa, saliva, dental plague, gingival crevice, tonsils and pharynx. However, these seemingly normal commensals become invasive or virulent as a result of weakened immune defenses.
Besides being indicators of progression to AIDS defining conditions, these oral lesions are universal components of HIV classification and staging schemes.
Oral lesions associated with HIV/AIDS have been said to occur between 30 to 80 percent of patients with this infection. Late presentation, a high viral load and lower innate immunity as a result of environmental and dietary factors are other possible reasons for the wide differences in the observed incidence of the orofacial manifestation of HIV/AIDS
These oral lesions include; fungal infections, bacterial infections, viral infections, neoplasms and miscellaneous conditions like hypermelanotic pigmentation of the oral mucosa, which though present in people not infected with HIV, occur more frequently and more severely in patients affected with HIV infection
Fungal infections have been found to be prevalent in patients with HIV/AIDS and this has been attributed to excessive use of antibiotics to combat bacterial infections or are as a result of cross infection following poor personal hygiene.