Dermatology consultation with a tablet in a bright clinic room.

Guides

Diagnosis Guide

Orientation for the path to diagnosis and clinical conversations.

60-second summary

If you only remember five things, remember these:

  • A diagnosis of Acne Inversa rests on the pattern of your symptoms, not on a single lab test or scan.
  • What matters most: typical lesions, typical sites such as the armpits, groin, buttocks or under the breasts, and whether they keep recurring.
  • Clinicians distinguish HS from boils, folliculitis, abscesses, or a pilonidal sinus.
  • Many people wait years for a diagnosis, often because individual nodules get described as isolated one-off events.
  • Preparing a timeline of locations and recurrences makes that pattern visible in the appointment.

A diagnosis is not a label — it is the route to appropriate treatment, and often an explanation for symptoms that went unexplained for a long time.

There is no test that proves HS on its own. Severity and future course are only loosely predictable early on.

Before your appointment, note where, how often, and how long symptoms occur — including the quiet periods in between.

Track symptoms and patterns

This summary is written and updated together with the full text. The evidence, limitations and sources stay unchanged in the article below.

Continue to the detailed explanation

A diagnosis of Acne Inversa rarely starts with a single lab value. What matters is the pattern: which lesions occur, where they occur, and whether they recur.

This pillar page helps you organise what you've noticed and prepare for an appointment. It does not replace an examination, but it can stop recurring nodules from being described — and dismissed — as isolated one-off events.

What Is Acne Inversa?

Start here for the basics of the condition before a diagnosis conversation.

 Recognising early symptoms

Which early signs matter most when nodules keep coming back.

 Symptoms at a glance

Nodules, abscesses, tunnels, scarring, and typical body locations.

 Questions for the appointment

A checklist for conversations with dermatologists.

 Could This Be HS? Appointment Pack

Turn a recurring pattern — locations, timing, previous labels and treatment — into a one-page summary. No diagnosis generated.

What actually counts toward a diagnosis

German S2k clinical guidance describes diagnosis as a clinical judgement made through inspection, palpation, and — where needed — assessment of tunnels under the skin. What matters most: painful inflammatory nodules, abscesses, tunnels, and scarring at typical sites such as the armpits, groin, genital and perianal region, or under the breasts.

A single abscess does not prove HS. But when similar lesions recur, appear at typical sites, or have already left scarring or drainage, that pattern is worth raising directly.

  • Type of lesion: deep nodules, abscesses, weeping areas, tunnels, scarring
  • Location: skin folds and other recurrently affected areas
  • Timing: when symptoms began and how often they return
  • Burden: pain, movement, sleep, work, intimacy, and emotional impact

Why the path to diagnosis can be bumpy

Early HS can resemble boils, folliculitis, ingrown hairs, or cysts. On top of that, affected areas are often intimate or covered in daily life.

A clear timeline helps precisely because of this. Photos of flares, a list of affected sites, and notes on recurrence turn many separate moments into a recognisable disease pattern.

Diagnosis also means ruling other things out

Clinicians are not only checking whether HS is plausible. They are also considering which other causes could fit the location and course. For symptoms on the buttocks or in the perianal area, other conditions can become particularly relevant to rule out.

The goal is not self-diagnosis but a more precise description. Saying that a painful nodule has kept returning to the same spot for months gives more diagnostic context than the word 'pimple' alone.

Preparation

What you can gather before an appointment

A small amount of well-organised information usually helps more than a long list of unsorted details.

Timeline

Note the approximate onset, how often flares occur, and whether the same site was affected again.

Body map

Mark the armpits, groin, under-breast folds, buttocks, or other regions where symptoms have occurred.

Course

Note whether nodules opened, drained, left scarring, or felt like tunnels under the skin.

Burden

Describe pain, sleep loss, restricted movement, missed work, and emotional impact concretely.

Framing

Three ways diagnosis conversations get cut short

HS is easier to overlook when recurring symptoms only ever come up as isolated acute events.

Only describing today's nodule

The current finding matters, but recurrence and earlier sites are what give the appointment depth.

Downplaying pain

Pain is not incidental. It can substantially affect daily function and belongs in the history.

Letting shame shorten the description

Intimate locations are medical information. They can be named factually and without justification.

Questions to bring to a diagnosis appointment

  1. Does the pattern of my symptoms fit Acne Inversa or Hidradenitis Suppurativa?
  2. Which findings support that, and which alternatives are you considering?
  3. How will we document severity, affected regions, and progression?
  4. What warning signs should bring me back sooner than a routine follow-up?

A previous pilonidal sinus is worth mentioning

  • Pilonidal sinus disease (a cyst or tunnel near the tailbone) is strongly associated with HS, and research suggests it can sometimes appear years before HS is recognised.
  • Having had one does not mean you have HS — it becomes relevant history only alongside a recurring pattern of lumps or drainage elsewhere.
  • Mention it together with where and how often those lumps recur, rather than as an unrelated detail from an earlier visit.

When not to wait for the next routine appointment

  • Fever, rapidly spreading redness, or a marked decline in how you feel overall
  • Sharply increasing pain that makes sitting, walking, or moving your arms difficult
  • A wound that is spreading, bleeding heavily, or that you cannot manage safely

Internal links

What Is Acne Inversa?

The basics, course, and typical symptoms in one introduction.

 Pilonidal Sinus and HS

Why a previous pilonidal sinus can be useful history when other HS symptoms are present.

 Acne Inversa in the groin

What can be observed at this typical location.

 Acne Inversa under the arms

Why movement and friction make symptoms there especially visible.

 Treatment Options

What a diagnosis leads to: treatment classes and shared decisions.

Key sources for this pillar page

  1. S2k guideline on the therapy of hidradenitis suppurativa / acne inversa AWMF, 2024
  2. North American clinical management guidelines for hidradenitis suppurativa, Part I Journal of the American Academy of Dermatology, 2019
  3. Hidradenitis Suppurativa U.S. Food and Drug Administration, content current as of October 15, 2024