Basic check-up: who’s who

With over 20 years’ experience in the field, DIAGNOSTIK ZENTRUM Fleetinsel Hamburg is the leading institute for preventive health care. We provide top quality preventive medicine.

Our team is led by Dr. Tomas Stein, Dr. Claus Friedrich Zimmer, Dr. Catharina Bidlingmaier and Dr. Hermann Johenning, each of whom is a qualified specialist in his or her medical field. They are supported by our professional office and marketing staff and skilled medical technicians. For particular examinations we can also call on additional medical specialists to support our long established team.

Dr. med. Tomas A. Stein

Dr. med. Tomas A. Stein

Specialist in internal medicine / cardiology
Medical Director, DIAGNOSTIK ZENTRUM Fleetinsel Hamburg


  • Medical Director and majority shareholder at DIAGNOSTIK ZENTRUM Fleetinsel Hamburg since 1998
  • Specialist in internal medicine / cardiology since 1994
  • 1992: research at St. George’s Hospital London
  • From 1984: at Second Medical Department (cardiology) of Asklepios St Georg hospital in Hamburg, specialising in echocardiography (ultrasound examination of the heart) and electrophysiology (heart rhythm disturbances)
  • 1982: research at Mount Sinai hospital, New York
  • 1976 – 1984: student of medicine in London and Cologne


  • German, American and European cardiology and preventive medicine societies
  • German society for ultrasound in medicine (DEGUM)
Dr. Catharina Bidlingmaier

Dr. med. Catharina Birdlingmaier

Specialist in internal medicine / cardiology at DIAGNOSTIK ZENTRUM Fleetinsel Hamburg


  • At DIAGNOSTIK ZENTRUM Fleetinsel Hamburg since April 2008
  • April 2009: qualified as specialist in nutritional medicine
  • 2006 – 2008: cardiology in independent practice
  • April 2007: qualified as specialist in cardiology
  • 2005 and 2006: assisting trainee, cardiology department, Itzehoe hospital (Prof. Kentsch)
  • 2004 and 2005: assisting trainee, cardiology in independent practice
  • June 2003: qualified as specialist in internal medicine
  • 1997 – 2003: assistant doctor at KEH Hospital, Berlin (Prof. Schulte)
  • 1994 – 1997: assistant doctor at Charité university hospital, Humboldt University, Berlin, First Medical Department (cardiology, angiology and pneumology, Prof. Baumann)
  • 1988 – 1994: medical student at Free University and Humboldt University, Berlin


  • German society for internal medicine
  • German Cardiology Society

Dr. med. Hermann Johenning

Specialist in internal medicine / gastroenterology and dietetics at DIAGNOSTIK ZENTRUM Fleetinsel Hamburg


  • Specialist at DIAGNOSTIK ZENTRUM Fleetinsel since November 2010
  • 2007 – 2010: specialist at gastroenterology department of Altona Asklepios hospital (Prof. Friedrich Hagenmüller)
  • From 2005: specialist in gastroenterology, nutritionist
  • From 2004: specialist in internal medicine
  • 1998 – 2007: gastroenterology department of Münster university hospital (Prof. Wolfgang Domschke)
  • 1991 – 1998: student of medicine at University of Münster (WWU)


  • German society for internal medicine
  • German society for digestive and metabolic diseases
  • German endocrinology Society
  • German society for ultrasound in medicine (DEGUM)
  • German nutrition society (DGE)
Dr. med. Anke Wesselmann

Dr. med. Anke Wesselmann

Specialist in ophthalmology

Trained as specialist in ophthalmology at Kiel eye clinic (Prof. Uthoff)


  • Professional society of ophthalmologists, Germany
  • German Ophthalmological Society
  • Quality Circle Hamburg north
Dr. med. Désirée Hölscher

Dr. med. Désirée Hölscher

Specialist in dermatology

Studied medicine at Hamburg University and anaesthesiology and intensive medicine at Neukölln hospital, Berlin, qualified as specialist in anaesthesiology.

Has been working as a dermatologist for over 10 years, initially at Dermatology Department, Hamburg Eppendorf university hospital, where she qualified as a specialist in dermatology and venereology, and subsequently at Dermatologikum skin clinic, Hamburg, where she has been a partner since 2001.

Additional qualification as allergist.

Dr. Sven A. Clausen

Dr. Sven A. Clausen

Personal Training – Sport für Hanseaten®
Medically qualified human movement scientist


  • Diploma and doctorate, Hamburg University, medically qualified human movement scientist
  • Lecturer on health matters for public health funds, private institutions and other audiences
  • Publications on movement science approaches to leadership training, Institut für bewegungswissenschaftliche Anthropologie
  • Lecturer and director of adult training
  • Scientific member of health commission of German sports science association (dvs)
  • Head of muscle and mobility section of medical check-up at DIAGNOSTIK ZENTRUM Fleetinsel Hamburg

All information on basic check-up

Our network of medical specialists

Dr. med. Ingke Andreae
Dr. med. Björn-Georg Neumann

Specialists in ear, nose and throat medicine, voice and speech disorders

Ruth-Maria Beckenbauer

Psychologist, psychotherapist /naturopath, recognised BDP supervisor, coach

Dr. med. Detlef Becker-Capeller

Specialist in internal medicine, rheumatology, physical and rehabilitation medicine
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Dr. med. Jutta Lübbering-Schmidt
Dr. med. Eva-Maria Baumgartner
Ulrike Rönck

Dr. med. Katja Sommer

Medical practice for diagnostic mammography
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Dr. med. Dr. med. dent. Dieter Edinger

Specialist in oral, maxillary and facial surgery
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Dr. med. Markus Flotho

Specialist in general and rescue medicine
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Dr. med. Isolde Frieling

Doctor and Osteologist (DVO) at Osteoporosezentrum Neuer Wall, Hamburg
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Dr. med. Christine Gebhardt

Specialist in surgery and vascular surgery at Klinik Fleetinsel Hamburg
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Dr. med. Holger Görike

Specialists in radiology
Radiologie am Fleet
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Prof. Dr. med. Jörn Sandstede

Specialist in radiology
Radiologische Allianz
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PD Dr. med. Achim Hedtmann
PD Dr. med. Michael Muschik

Specialists in orthopaedics
Klinik Fleetinsel Hamburg
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Jutta Kraemer


Dr. med. Andreas C. Pauly

Private family practice
Specialist in natural and nutritional medicine

Dr. med. Wolfgang Reinpold

Specialist in general, visceral and trauma surgery
President of the German Hernia Society
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Dr. Anna von Schrenck

Specialist in ophthalmology
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Dr. med. Jürgen Walpert
Dr. med. Roland Sellckau

Specialists in orthopaedics, sports medicine and chiropraxy at Klinik Fleetinsel Hamburg

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If surgery or any other invasive procedure proves to be necessary we work with top clinics and specialists to ensure you receive the best possible treatment and further care.

  • Klinik Fleetinsel Hamburg: specialist orthopaedic clinic for spine, joint and foot surgery, sports medicine, general surgery and vascular surgery.

  • Hanseatisches Herzzentrum Hamburg: provider of high performance medicine e.g. heart surgery, cardiology and catheter ablation for heart rhythm disturbances, trauma centre specialising in spine surgery.

  • Dermatologikum Hamburg: Europe’s largest specialist clinic for the diagnosis and treatment of skin diseases.