Histologically confirmed tuberculosis-associated obstructive pulmonary disease

Although chronic airflow limitation (CAL) is an important long-term consequence of tuberculosis (TB), little is known about the disease process. We present what we believe to be the first case of histologically confirmed residual TB-associated obstructive pulmonary disease (TOPD) in a 23-year-old non-smoking man who developed severe CAL after one episode of TB, with no other plausible risk factors. Lung biopsies identified residual post-TB pathology affecting the small airways and vessels throughout his lung; this has not been reported previously. These findings strengthen the argument that TOPD may be a phenotype of CAL distinct from both smoking-related chronic obstructive pulmonary disease and bronchiectasis.

Pulmonary cholesterol crystal embolization

BACKGROUND

Cholesterol crystal embolization (CCE) has been documented to affect nearly every organ system. However, CCE involving the lung is distinctly uncommon and has been documented only in the setting of an aortocaval fistula.

DESIGN

A case at the Massachusetts General Hospital and a MEDLINE search of English-language medical articles published between 1966 and 1997 provide the basis for this report.

RESULTS

The precipitants of CCE include invasive vascular procedures, anticoagulant therapy, and thrombolysis. The most common symptoms include claudication of the calf, gastrointestinal bleeding, and weight loss. The most common signs include livedo reticularis, gangrene, and ulcers. Azotemia, proteinuria, normocytic anemia, and eosinophilia often are found. Herein is described the first pathologically confirmed case of CCE to the lung in the absence of an arteriovenous fistula.

CONCLUSION

Pulmonary hemorrhage should now be included in the diverse list of presenting signs of CCE. Moreover, CCE should be considered in the differential diagnosis of pulmonary-renal syndromes.

Calcium-induced release of 5-hydroxytryptamine from thyroid lobes in vitro and accompanying ultrastructural changes in parafollicular and follicular cells

Biogenic amines, including serotonin (5-HT), have been shown to activate follicular cells of the thyroid. 5-HT is stored in bat's parafollicular cells. Previous radioautographical evidence indicates that this 5-HT is present in calcitonin granules. The present study was done to determine if Ca++, the natural stimulus to calcitonin release, would also release parafollicular cell 5-HT and, if so, whether this release would be accompanied by activation of follicular cells. Parafollicular cells were filled with labeled 5-HT by incubation of thyroid lobes of bats or mice with 5-[3H]hydroxytryptophan, the precursor of [3H]5-HT. Thyroid lobes were incubated in vitro in Ca++-free medium containing a chelating agent and were then challenged with Ca++ (0-30 mM). Release of [3H]5-HT was defected beginning at 5 mM Ca++. [3H]5-HT release was roughly proportional to the Ca++ concentration. Calcium challenge also affected thyroid ultrastructure in bats. After 10-min exposure to 30 mM Ca++, there were an increased number and centripetal movement of follicular cell lysosomes, development of apical pseudopods, and formation of colloid droplets. Many lysosomes also developed a crystalline-like matrix. An unique membrane-enclosed, rod-shaped organelle appeared in a small number of follicular cells. Parafollicular cells exposed to high concentrations of Ca++ were often degranulated, although many appeared unchanged. These changes confirm that 5-HT is released from parafollicular cells by elevating the external Ca++ concentration, supporting the hypothesis that 5-HT and calcitonin share storage granules. 5-HT release may mediate the activation of follicular cells by Ca++.

Multiple peripheral pulmonary carcinoids and tumorlets of carcinoid type, with restrictive and obstructive lung disease

Multiple peripheral carcinoid tumors were found on lung biopsy in a 53 year old woman with an eight year history of pulmonary nodules. The biopsy specimen showed nodules varying from 1 to 7 mm in greatest diameter. The larger lesions were typical bronchial carcinoids whereas the smaller ones resembled pulmonary "tumorlets." Electron microscopy showed neurosecretory granules typical of carcinoids. The common multicentric origin of carcinoids and tumorlets from Kulchitsky cells is discussed. Pulmonary function testing revealed mild obstructive and restrictive defects, both attributed to the carcinoid tumors. The history, pathology and physiology of this unusual case are presented in detail, with a review of the literature. Obstructive airways disease, presumably due to the extensive bronchiolar involvement, has not previously been reported in this entity.