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W M Tsui

Publications and source records attributed to W M Tsui.

25 records · Page 2Linked to original sources

Disseminated Penicillium marneffei infection in HIV-infected subject.

Penicillium marneffei is a rare human pathogen predominantly affecting residents of South-east Asia. We report four fatal cases from Hong Kong in human immunodeficiency virus-infected patients. The diagnosis was established by histological examination and confirmed by isolation of the fungus. The infection was disseminated with involvement of lymph nodes, liver, spleen, lung, intestine and bone marrow. The involved organs showed an exclusively anergic tissue reaction characterized by a diffuse infiltrate of fungi-laden macrophages, multiple co-existing opportunistic infections and lymphoid cell depletion. This organism has to be distinguished from Histoplasma capsulatum and Pneumocystis carinii. Establishment of the diagnosis is important not only because this infection is potentially curable, but also it is a likely indicator disease of AIDS in South-east Asia. Penicilliosis marneffei should be suspected in any symptomatic HIV-positive patient who comes from or has visited endemic areas of South-east Asia.

Aged↗

Liver changes in reactive haemophagocytic syndrome.

Hepatomegaly and deranged liver functions are common findings in reactive haemophagocytic syndrome (RHS). We report the findings of 12 fatal cases of RHS in which histological materials of the liver are available for study. The underlying diseases of these patients included lymphoma/leukaemia (6 cases), disseminated undifferentiated carcinoma of the ovary (1 case), disseminated nasopharyngeal carcinoma complicated by tuberculosis (1 case), adenovirus pneumonia (1 case), pneumococcal pneumonia (1 case), typhoid fever (1 case), and possible drug intoxication (1 case). Ten patients had involvement of the liver by the underlying disease process which contributed to the marked hepatic derangement. Non-specific reactive hepatitis, sinusoidal dilatation and steatosis resulting from systemic or local effects of the associated diseases and the haemophagocytosis also added to the high incidence of liver abnormalities. A diffuse Kupffer cell hyperplasia with haemophagocytosis is characteristic of the syndrome, as all the cases showed increased numbers of bland-looking histiocytes within the hepatic sinusoids and haemophagocytosis which was moderate to marked in 8 cases and mild in 4. Thus the finding of Kupffer cell hyperplasia with prominent haemophagocytosis in liver biopsy is indicative of an element of RHS and warrants clinical monitoring. Differential diagnoses of haemophagocytosis in liver are also discussed.

Adolescent↗

Solitary necrotic nodule of the liver: parasitic origin?

AIMS: To report further cases of solitary necrotic nodule of the liver and to study its nature. METHODS: Seven nodules were retrieved from 4000 necropsy and surgical liver specimens coming to light over the past five years. All of them satisfied the diagnostic criteria of solitary necrotic nodule: a solid lesion with a central necrotic core and a hyalinised fibrotic capsule containing elastic fibres. Their clinicopathological features were reviewed. RESULTS: The nodules were incidental findings at surgery or necropsy in four men and three women whose ages ranged from 48 to 79 years (mean 63.7 years). Four were found in the right lobe and three in the left. Six were subcapsular and only one deep in the parenchyma, with sizes ranging from 0.3-2.5 cm. Each of them was solitary, well demarcated, and round to oval with a firm, whitish rim and a core of yellowish white cheese-like to solid material. In addition to the basic architecture, there were a number of common and undescribed histological features: presence of varying numbers of small mural vessels with intimal fibrosis and obliteration, presence of cholesterol clefts and foamy cells among necrotic material, and sparsity of inflammatory cells. In the two cases where ghosts of degenerated cells and partially preserved liver reticulin pattern were noted, worms were identified, one being Clonorchis sinensis. CONCLUSIONS: The entity is believed to be a "burnt-out phase" of a variety of benign lesions. Parasitic infestation is another possible cause, and presence of ghosts of degenerate cells, partially preserved liver reticulin pattern, cholesterol clefts and foamy cells among necrotic material are auxiliary features pointing to such an aetiology. The variation in morphological fine details reflects both the lesion's diverse pathogenesis and the fact that it can be of varying duration.

Aged↗

Endocrine cell hyperplasia of the uterine cervix. A precursor of neuroendocrine carcinoma of the cervix?

A 33-year-old woman who presented with vaginal bleeding was diagnosed to have neuroendocrine small cell carcinoma based on cervical smear and biopsy. Hysterectomy was performed, and a tumor measuring 5.5 X 2 mm was found at the squamocolumnar junction of the uterine cervix. In the immediate vicinity of the tumor, there was proliferation of cytologically benign endocrine cells in the normal endocervical glands and in the glands showing intraepithelial glandular neoplasia. Both the hyperplastic endocrine cells and the invasive tumor cells showed argyrophilia and immunostaining for neuron-specific enolase, neurofilament, and chromogranin. The topographical relationship suggests that endocrine cell hyperplasia may represent a precursor of neuroendocrine carcinoma of the cervix.

Adult↗

Fine needle aspiration diagnosis of angiomyolipoma of the liver using a cell block with immunohistochemical study. A case report.

Fine needle aspiration diagnosis of hepatic angiomyolipoma has been reported rarely. Below we report one such case diagnosed by examination of a cell block. The presence of epithelioid smooth muscle cells, mature adipocytes, thick-walled vessels and extramedullary hematopoiesis established the diagnosis. It was further substantiated by positive staining of the epithelioid cells for muscle-specific actin (HHF-35). The epithelioid cells were also immunoreactive with a melanocytic marker, HMB-45, but not with desmin, vimentin, cytokeratin or S-100 protein. HMB-45 might prove to be a sensitive marker for the epithelioid smooth muscle component of the tumor. The advantage of the routine use of a cell block in fine needle aspiration is emphasized.

Actins↗