Unexplained cardiac failure leading to the identification of a Belgian family affected by hereditary amyloidosis.

We report the diagnosis of hereditary amyloidosis that affected a Belgian family that was initially diagnosed in a 73 year old woman. This patient was admitted with complaints of congestive heart failure. Cardiac work-up showed myocardial hypertrophy with zones of hyperintensity, suggestive for amyloidosis that was confirmed on a rectal biopsy. A hereditary form of amyloidosis was found by showing the Val30Met mutation within the transthyretin gene, that was also found in her asymptomatic son. This case shows that genetic testing is crucial in cases of unexplained amyloidosis and can help in the diagnosis and follow-up of patients and family members.

[Invasive pulmonary mucormycosis with invasion of the thoracic spine in a patient with myelodysplastic syndrome]. / Mucormycose invasive du poumon et du rachis dorsal.

We report the case of a 67-year-old patient who presented with a myelodysplastic syndrome and who developed a pulmonary mucormycosis with a rare extension to the dorsal spine. A decompressive laminectomy was attempted after failure of broad-spectrum antifungal treatment (Cancidas, V-Fend). The diagnosis was obtained after surgical biopsy. The scheduled lobectomy could not be performed because of altered clinical condition. The patient eventually died despite adapted antifungal treatment (Abelcet, Posaconazole). Pulmonary mucormycosis is a rare cause of mycotic infection that reaches most of the time immunocompromised patients. The pathogenic agent is part of zygomyces that have angio-invasive ability. Perineural propagation was recently described. Immunodepression, late diagnosis and lack of response to new generation antifungal drugs (V-Fend, Cancidas) are responsible for therapeutic failure in this disease. This case emphasizes the risk inherent to empirical antifungal treatment and the need of early biopsy in cases that do not respond to treatment.

Evaluation of atrial vulnerability with transoesophageal stimulation in patients with atrioventricular junctional reentrant tachycardia. Comparison with patients with ventricular pre-excitation and with normal subjects.

The aim of our work was to evaluate the inducibility of atrial fibrillation in a group of patients with atrioventricular junctional reentrant tachycardia and to compare it with that of patients with a Kent-type ventricular pre-excitation (Wolff-Parkinson-White syndrome) and a control group. One hundred and twenty-five subjects were separated into groups. Group 1 comprised 49 Wolff-Parkinson-White patients, with a mean age of 26.4, range 10-66 years; group 2, 51 patients with atrioventricular junctional reentrant tachycardia inducible by transoesophageal atrial stimulation and/or clinically documented, with a mean age of 43.4, range 16-78 years; group 3, 25 control subjects with a mean age of 26.4, range 13-76 years. Each subject underwent atrial transoesophageal stimulation with the following protocol: programmed atrial stimulation with 1 and 2 stimuli during atrial pacing of 100.min-1 and 150.min-1; atrial stimulation for 10 s at a rate of 200-300-400-500-600.min-1 with intervals of 10 s between stimulations, five successive 'ramp-up' atrial stimulations for 9 s with the rate increasing from 100 to 800.min-1 with intervals of 10 s between stimulations. The end point was the completion of the protocol or induction of sustained atrial fibrillation (> 1 min). The chi-square test was used for statistical analysis. Our results showed that in group 1 atrial fibrillation was induced in 27/49 patients (55.1%); this was sustained in 13/49 (26.5%) and non-sustained in 14/49 (28.5%); in group 2, atrial fibrillation was induced in 22/51 patients (43.0%); it was sustained in 7/51 (13.7%) and non-sustained in 15/51 (29.4%); in group 3, sustained atrial fibrillation was not induced in any subject and in only one subject was a non-sustained atrial fibrillation (4 s) induced. The chi-square test showed that group 2 vs group 1 were non-significant, while group 2 vs group 3 and group 1 vs group 3 were significant (P < 0.003 and P < 0.0007, respectively). Therefore group 2 patients showed a greater atrial vulnerability in comparison to the control subjects and a similar vulnerability to group 1 patients. It is possible that the greater atrial vulnerability in the patients of group 2 was due to the double nodal pathway.

Effect of bromocriptine on thyroid hormone-induced growth hormone production in cultured GH1 cells.

L-triiodothyronine induces a three-fold increase in growth hormone production in cultured GH1 cells. The dopaminergic agonist, bromocriptine, inhibits the thyroid hormone-induced growth hormone production to the level of that produced by the control cells. This effect can be observed within eight hours of incubation and persists as long as forty-eight hours in culture and is not due to a change in cell population. In contrast, bromocriptine appears to have no effect on growth hormone production in the control cultures. The estimated concentration of bromocriptine which gives a half-maximal inhibitory effect is 0.3 nM, and concentrations above 5 nM give a complete inhibitory effect. The intracellular growth hormone concentration represents only a very small fraction of total hormone production and does not appear to be influenced by bromocriptine. Therefore, the inhibitory effect of bromocriptine on growth hormone production in thyroid hormone treated cultured GH1 cells may result from its action on the synthesis of growth hormone.