No studies investigating the size and secretion rate of the apocrine glands in health and disease are known to this author. The existence of plugged follicles in hidradenitis suppurativa has been accepted histologically since   Shelley  and  Cahn's  original work  on  the pathogenesis of the condition. More recently Highet et al  and  Mortimer  have  stressed  the  common occurrence of comedones in hidradenitis suppurativa but their  production and relationship to inflamed lesions is not known. Microbiological analysis of hidradenitis suppurativa gives  no consistent results.  In early disease no  pathogens   are identified  but,  given  the appropriate environment, the normal skin flora could, as in acne, mediate inflammation. There is clearly scope for much  research.

   The most recently investigated aspect of hidradenitis suppurativa is  systemic hormone levels: plasma  testosterone  (as measured by the free androgen index, for example) is significantly higher  in patients compared to controls though there was considerable overlap between some patients and controls. These data suggest  that plasma androgens are permissive and that there may be end-organ hyperresponsiveness which explains the disease and its severity.

  Dvorak et al found that in hidradenitis suppurativa no abnormality was demonstrated in any granulocyte or cell-mediated immune function tests. All patients had normal  immunoglobulin levels and  elevated  total haemolytic complement. It was concluded that hidradenitis suppurativa is a localized chronic inflammation of apocrine glands without a generalized  defect in host defence.

  Mortimer concluded that patients with hidradenitis suppurativa appear to have endocrine abnormalities sufficient  to suggest an androgenic basis  for this disease.31 In this  way hidradenitis suppurativa falls into the  same  category  as acne vulgaris and  idiopathic hirsutism:  endocrinologically  representing  a  heterogeneous group, with no single endocrinological abnormality determinable in every patient. Treatment Diagnosis and treatment before  undermining  sinus tracts and burrowing abscesses have developed is crucial for satisfactory control of the disease. Identification of comedones  in  affected and nonaffected  apocrine sites, as well as retro-auricular areas, is important for mni early  recognition.  The  response to  treatment  in  the early  or intermediate stages with longterm antibiotics (six months or more) is variable and at times frankly disappointing. Nevertheless, they should be tried. Tetracycline (1 g/day), minocycline (100 mg/day) or clindamycin (600  mg/day) being the drugs of choice.

  An exciting new development for  females with hidradenitis suppurativa is the use of anti-androgens .39'40 In  order to  examine whether antiandrogen therapy was effective in hidradenitis suppurativa, ethinyloestradiol  50 i^g/cyproterone acetate  50 mg in a reverse sequential regimen was compared with ethinyloestradiol 50  (j,g/levonorgestrel 250 |xg  (Eugynon 50) in twenty-four female patients. Both treatments produced substantial improvement in disease activity: overall, 38 per cent  of patients were cleared  and have remained free of disease for  eighteen months;  29  per cent of patients improved; 20 per cent remained  unchanged;  while 12  per cent  deteriorated. Clinically, cyproterone acetate was not significantly more effective than Eugynon  50.  This author's department has  also used, in an uncontrolled study, spironolactone - up to 200 mg/day -  and obtained some clinical benefit in about  50  per cent of  patients.  Unfortunately, these hormonal regimens have  too  many  anti-androgenic side-effects to be given to males.

  The role of isotretinoin in hidradenitis suppurativa is controversial but most centres consider it of little or no benefit except possibly in doses of 2  mg/kg/day for even up to two years. However,  Boer concluded that the use of retinoids  should be  considered even  though the response rate is only 30-50 per  cent.41 He suggested that another approach might be to combine isotretinoin therapy with other forms  of treatment such as  oral antibiotics, oral corticosteroids  or  intralesional corticosteroid injections.

  Data presented by Hughes (personal communication 1988) based on a survey of 150 patients with hidradenitis suppurativa indicate that surgery is unquestionably of value  in patients with moderate  to severe disease. Excision of the area affected (plus a 2 cm rim of normal tissue) in the axilla and perineum is  of  considerable benefit. In the perimammary area wide excision of the individual lesions is preferable. Healing by granulation tissue  is  preferred  to  grafting  but occasionally mesh grafts are indicated.

Thus,  hidradenitis suppurativa  often benefits from early  diagnosis  and  good  collaboration   between surgeons and dermatologists in an attempt to control what can be, at times, a physically and psychologically devastating disease.