Studies and case reports

Single sting (re-exposure)
Apis mellifera, Vespula germanica
Van der Linden et al. 1993: 138 patients who had a history of an anaphylactic reaction to hymenoptera stings were re-exposed to a sting from the same hymenoptera species (Apis mellifera, Vespula germanica) under controlled clinical conditions.

Multiple stings
Apinae
Bousquet et al. 1984: 1 case with 65 stings.
Meszaros 1970: 1 case with >2,500 stings.

Apis mellifera scutellata ("Killer" bees, Africanised honey bees)
Brazil
Franca et al. 1994: 5 cases with estimated numbers of stings from >200 (3/5) to >1,000 (2/5). Identification: morphological 2/5; with the help of indirect criteria 3/5.

Signs & symptoms

Autopharmacological effects

Single sting (re-exposure, see above)
Apis mellifera, Vespula germanica

Classification:

0     No systemic reaction.
I      Skin symptoms (generalised urticaria, itching, erythema).
II     Gastrointestinal symptoms (abdominal or chest pain, nausea, vomiting), generalised oedema.
III    Respiratory symptoms (respiratory distress, difficulty in swallowing, hoarseness, stridor).
IV    Arterial hypotension (defined as a fall in pressure of 15 mmHg compared to the mean initial arterial blood pressure) that required

       immediate intervention, with or without other cardiovascular symptoms, such as cyanosis, collapse, arrhythmias or angina pectoris.

Results of the re-exposure:

Of 26 patients who had a history of a grade I reaction, 23 had no reaction (grade 0) upon re-exposure and 3 had a grade 1 reaction.

Of 39 patients who had a history of a grade II or III reaction, 32 had no reaction (grade 0) upon re-exposure, 5 a grade I reaction and 2 a grade II or III reaction.
Of 73 patients who had a history of a grade IV reaction, 44 had no reaction (grade 0) upon re-exposure, 10 a grade I reaction, 2 a grade II or III reaction and 17 a grade IV reaction.
Conclusion: 28% of patients who have a history of an anaphylactic reaction to hymenoptera stings suffer another anaphylactic reaction upon re-exposure (Van der Linden et al. 1993).

Multiple stings
Apinae
Angio-oedema of the face with burning pain and pruritus within 5 min following multiple stings that spread to the trunk and lower extremities within 4 h; abdominal pain (Bousquet et al. 1984).

Apis mellifera scutellata
Extensive oedema of the skin (Franca et al. 1994).

Local effects

See above (Autopharmacological effects).

Haemostatic and haemolytic effects

Multiple stings
Apinae
No clinical signs of haemolysis (Bousquet et al. 1984).
Icterus associated with oliguria (Meszaros 1970).

Apis mellifera scutellata
Haemorrhages, haemolysis (Franca et al. 1994).

Muscular effects

Multiple stings
Apinae
No clinical signs of rhabdomyolysis (Bousquet et al. 1984).

Apis mellifera scutellata
Rhabdomyolysis 4/5 (Franca et al. 1994).

Renal effects

Multiple stings
Apinae
No clinical signs of acute renal failure (Bousquet et al. 1984).
Oliguria (Meszaros 1970).

Apis mellifera scutellata
Acute renal failure 3/5 (Franca et al. 1994).

Other signs & symptoms

Apis mellifera scutellata
Arterial hypertension, possibly as the consequence of venom-induced catecholamine release via melittin and phospholipase A₂ 3/5, hepatocellular necrosis 2/5, ARDS/pulmonary oedema 1/5 (Franca et al. 1994).

Case fatality rate

Apis mellifera scutellata ("Killer" bees, Africanised honey bees) 3/5. Death occurred within 22–71 h. Histopathology: ARDS, hepatocellular necrosis, acute tubular necrosis, focal subendocardial necrosis, DIC (Franca et al. 1994).
See also General information on hymenopterans: Epidemiology.

Laboratory and physical investigations

1. Haemostasis
Blood clotting times slightly increased (Franca et al. 1994).

2. Leucocytes
Marked neutrophilic leucocytosis (Franca et al. 1994).

3. Liver values
AST, ALT increased (Franca et al. 1994).

4. Myoglobinuria, CPK
CPK, in particular CPK-MM, increased (Franca et al. 1994).

5. Renal function
Creatinine increased (Franca et al. 1994).

First aid - treatment

Multiple stings
Apis mellifera scutellata

Despite treatment with antihistamines, corticosteroids, bronchodilators, vasodilators, bicarbonate, mannitol, artificial respiration and intensive medical care 3/5 patients died (Franca et al. 1994).

Recommendations (Franca et al. 1994):

• Immediate removal of any stings left in the skin.
• Pigment nephropathy: early use of bicarbonate and mannitol.
• Acute renal failure: dialysis.
• Hyperkalaemia (acute renal failure, rhabdomyolysis): dialysis and other potassium-lowering methods.
• Hypercatecholamine syndrome: prazosin, nifedipine (analogous to the treatment of scorpion envenoming).
• Histamine release and inflammatory effects of envenoming: antihistamines and corticosteroids.
• Severe signs of envenoming within a short period after a large number of stings: possibly exchange transfusion or plasmapheresis.