To many people, acne will be synonymous with teenage spots. Once you have made the painful transition from childhood to adult, acne is no longer an issue. The reality is that acne affects all age groups, from newborn babies to adults, but because the overwhelming majority of cases of acne occur during adolescence, inevitably this age group is the focus of most people\'s attention. It has to be said that for a doctor, teenage acne is the least interesting of all the types of acne. Sadly, many teenage acne sufferers fit the stereotype of being both spotty and stroppy, so it is perhaps unsurprising that most family doctors, who typically will have upwards of 50 adolescent acne sufferers to cope with at any one time, fail to give these patients the time, care and attention that they warrant. The other clinical types of acne are much rarer and also, from a clinical point of view, much more interesting than adolescent acne. The type of acne that perhaps provokes most interest amongst doctors, although it must be stressed that this interest is sometimes of a prurient nature, is known somewhat affectionately as kinky acne, although technically it is a specific sub-type of the clinical form of acne known as acne caused by occlusion. The characteristic feature of all the different clinical types of acne is spots. Although the cause of the spots is different in the various types of acne, the mechanism by which the spots form is essentially similar, and involves a combination of one or more of the following elements - blocking of the sebaceous glands, the overproduction of sebum and colonisation of the sebaceous duct by the acne-promoting bacteria Proponiobacterium acnes. Experimentally, one can induce the formation of acne spots on human skin by the application of impervious sticking plaster for a period of a few days. This type of acne is a form of acne caused by occlusion, as it is the blocking of the sebaceous duct by the sticking plaster which produces the conditions under which the spots develop. Kinky acne is another form of acne caused by occlusion, although in the case of kinky acne the experimentation causing the acne tends to be of a sexual nature. People who indulge in sadomasochistic or bondage activities may spend long periods of time wearing tight fitting garments or restraints made of impervious materials such as PVC, latex, or leather. A high proportion of people indulging in sadomasochism or bondage for prolonged periods of time will develop acne on those areas where the surface of the skin is occluded by close fitting or restraining outfits or accessories. Most sufferers from kinky acne who consult a doctor have already guessed the diagnosis, as the distribution of spots will follow a characteristic pattern, which matches closely the garment or restraint that has caused it. Sufferers from kinky acne may be rather less pleased to discover that the only way to treat the complaint effectively is complete abstention from their unusual recreational activities until the spots clear. However, some doctors take solace from the fact that their masochistic acne patients may be gaining some additional pleasure from the discomfiture caused by their kinky acne. The other group that is at risk from a similar form of acne caused by occlusion are soldiers and sailors, particularly those serving in tropical or sub-tropical conditions. In these military cases of occlusive acne, it is the soldiers’ rucksack straps and webbing occluding the surface of the skin that are the cause of the acne. Hot, humid conditions exacerbate the problem, as soldiers are inclined to dispense with items uniform which usually protect the torso for direct contact with the rucksack straps and the atmospheric moisture and excessive sweating increases the macerating effect. Once again, removal of the cause of the problem, which in the case of the military means a period of light duties, is the only effective means of treatment and normally results in a rapid improvement in the condition. Soldiers, sailors and sadomasochists are perhaps uncomfortable bedfellows as sufferers from this rare and unusual from of adult acne, but fortuitously provide some light relief from the tedium of treating teenage acne.