Information to the "balloon disease" (Hydrops) of african dwarf frogs
  all contents such as text and pictorial material are subject to (c) Zwergkrallenfroesche.de

The empiric reports are not fully available in english yet. The report about hydrops is translated here:

First: I am not a veterinarian, biologist or zoologist. I collected this information from different sources and hope it is useful for the ADF keeper in case of an ill african dwarf frog. It ist written as objective as possible so that anybody can bild an own opinion. The intention to create this page was that I didn`t found any vetenarian who could help me with this subject so I was forced to help the frog by myself. After I tried to heal the froggy I met Prof. Dr. Grunz at the zoophysiological institution in Essen. He told me that the method I used seemed to be OK since he didn`t know any other way. But he pointed out, that Hymenochirus or Xenopus kinds have got a very sensitive skin which can be hurt easily. He recommendet to use handgloves for this reason. Moreover handgloves would protect the human from possible allergy against the mucous membrane of the frog.

   Contents:
   General information to the disease
   Treatment

In [1] it is mentioned that it concerns of Hydrops, whose symptoms consits of the fact that the animal looks like a ballon filled with water, and whose cause is a malfunction of the lymphatic hearts which normally pump the lymph from the lymphatic vascular system.

What is lymph? The lymph is a lymphocytes containing liquid. (Lymphocytes are certain white blood corpuscles, that form a part of the immune system.) This clear, easily yellowish liquid reaches the cell gaps by filtrtation thru the blood capillaries. It is derived from there by the lymphatic system. Lymph serves on the one hand the transport of nutrients into the tissue and on the other hand the evacuation of waste materials or also bacteria and damaged or died cells from the tissue.

What is the lymphatic vascular system? The lymphatic vascular system is a system of channels, coming out from the cell gaps, which collects the lymph withdrawing from the blood capillaries into the tissue and which supplies the blood circuit again with lymph if necassary. Surplus liquids, salts etc. in the blood circuit are secreted, over the kidneys and the urinary bladder as urine. With some kinds of birds, reptiles and amphibians (to those also the african dwarf frog counts) the liquid is pumped out of the lymphatic vascular system by contractive lymphatic vasculars, the lymph hearts. To the lymphatic system there is a very interesting site (german): link.There one finds also that a blockage of the lymphatic vascular system leads to Elephantiasis (lymphedema) (about this later).

If the lymph hearts fail, then the lymph remains in the lymphatic vascular system and the lymph accumulates increasingly in the lymph pockets. Thus the liquid presses on the organs and the lung, whereby the suffering animal finally dies.

In [5] it is described that directly under the skin are expanded lymph pockets, and that the lymph (propelled over lymph hearts) flows into the veins of the neck and haunch region.

The accumulation of lymph, caused by a handicap of the lymphdrain is also called dropsy (English designation of the Greek term Oedema), Lymphedema and Elephantiasis (Lymphatic Filariasis). With this base you can finds further information:

In [4] it ist written that edemas are observed at tadpoles and adult animals, and this usually with individual animals. Edemas are differentiated in three forms:
1.  Generalized edemas of the animal body
2.  Hydrops predominantly at larva stages
3.  Stout filled lymph pockets at salientians (Anura)
The cause is not so far clarified (however the Tadpole Edema Virus is assumed) and it does not exist promising therapy.

In the Roche medicine encyclopedia (4th edition) one finds about Hydrops (English dropsy): "diseased accumulation of liquid (trans or exudate) in body cavities (= H. verus) or in the interstitial area (increase of the extracellular fluid), more rarely also in the intracellular area, as an expression of a metabolic disturbance with false regularization of the water electrolyte household or a local disturbance of the hydrodynamic, osmotic and nervous regularizations at the blood tissue barrier (e.g. with inflammations, allergy); see. Edema. "

In [8] you can read about Aszites and Hydrops: A clearly visuable extension of the body cavity (the Zoeloms) refers to these diseases and it is recommended an injection of Furosemid (5mg/kg daily, distributes on two doses).
In case of  liver zirrhosis it can come to an accumulation of liquid in the free abdominal cavity between the organs. This "belly water" is called Aszites. For treatment a negative common salt and water balance must be achieved, i.e., the concerned individual must secrete more salt and water than it is supplied. If the salt balance is kept negative, the water elimination happens "automatically". The salt secreted with the kidney carries then the water forward. How you can use thes for healing the ADF unknown to me unfortunately.

In [9] it is described that edemas can be oftenly observed as side effects at different diseases e.g. with "Red Leg".Ther would be references on the fact that edemas are caused by a too low NaCl content of the water. This would fit then the statement that you could treat the disease with an addition of 1 teaspoon common salt on 5 litres water.
With edemas on adult animals an overstocking of the lymphpockets (see above) would occur, whereby the entire body appeard swollen (this is the accurate description of the "balloon disease"). It would be possible that only single animals are concerned and that these frogs survived for a long time. A medicamentous treatment is not indicated in this work (unknown), and a treatment by dotting is recommended here also. However they report there: "edemas at tadpoles of Xenopus laevis [a kind of the african claw frog] were affected successfully by an additive from NaCl to the water [… ] as supporting measure fight possibly existing intestine parasites"  In addition they write: "with embryos edemas arose in form of a Hydrops of ascites."

To Aszites (Hydraskos, belly water addiction) information in the Roche encyclopedia medicine ( 4.edition) is to be found likewise: link

Elephantiasis (Filariose, Lymphedema) is transferred by mosquitoes in the Tropics and caused by small worms (Filarien). Therefore I exclude this form here.

Because humans with lymphedemas are punctured, and a punction of the lymph pockets comes this nearby, it is probably the most attached form of treatment. In the following a few points to the punction:

Treatment:
First an important information right at the beginning: After I had accomplished the punction at the ADF, I found out by coincidence that there is a passage in the german law for animal protection, which sometimes forbids treatment of animals by non vetenarians. One finds the appropriate passage here (german). Please take care of similar laws in your country.

Concerning the punction you should consider the following things:

1. You should puncture the frog as soon as possible, because as time goes by the internal organs can be damaged by the high pressure.
2. You need a syringe (3-5ml), with a thin cannula (size. 20, 0,40 x 20 mmBl/LB 27 G x 3/4) and potassium permanganate solution as possible for disinfecting. Use latex handgloves please, because this helps preventing hurting the frogs mucous membarne. In addition it is very helpful if someone giving you a helping hand.
3. Puts the frog on the back on a smooth, clean, not absorbent pad as possible.
4. Then lay down your hand on the surface of the table in such a way it lies as calmly as possible, and the syringe trembles as little as possible. Then lead the cannula carefully into a thigh (where a lymph pocket is lokaded) (about 1.5 mm) and take the liquid off very carefully and in very small steps. The liquid from the remaining body flows into the thigh, so that you need only one dot. The whole lasts about 10-15 minutes. During this time someone should keep the frog damp through squeezing with water. If the frog itself moved (which with me wasn't the case), the assistant should hold the animal easily. A (wet) cotton glove can possibly help, which prevents slipping.
5. If the majority of the liquid is sucked off (now the skin hangs down quite flabby), then the frog is briefly put into the potassium permanganate bath, and set afterwards again in the quarantine basin. It is really not necessary that you make more than one puncture.

In the generally part (above) it is additionally reported of the possibility that you can affect the process of the disease by addition of NaCl (common salt) in the positive sense (dosage look above.). Finally, a picture of the frog immediately after the punction:

Georg Leithold, 20.05.2002.
Please write me, if you made experiences with this disease, or found appropriate information. I'm still looking for interesting links to this topic. Thank you.

Links:

• deutsch: Vorlesungsscript über Zoologie/Kreisläufe
• deutsch: Zucht und Haltung von Krallenfröschen (pdf)
• english:  Very intersting article about lymph heart function (pdf)
• english:  Another article about lymph hearts
• english:  xrefer - scientific search engine