Progression of collagenous colitis to ulcerative colitis.

Collagenous colitis is a form of microscopic colitis that results in chronic watery diarrhea. The disorder predominantly affects middle-aged women, and its course tends to be benign. It is not thought to be a precursor of overt inflammatory bowel disease; however, apparent progression to ulcerative colitis has been reported on one previous occasion. We describe two further patients with symptoms and histologic features of collagenous colitis who subsequently developed ulcerative colitis. The first patient developed ulcerative colitis 13 months after diagnosis of collagenous colitis, although she gave a 23-year history of profuse watery diarrhea, which had not been adequately investigated. In the second patient, collagenous colitis was diagnosed soon after the onset of watery diarrhea, and 12 months later, progression to ulcerative colitis was documented. Both patients tested positive for perinuclear antineutrophil cytoplasmic antibody after they developed ulcerative colitis; the first patient was initially negative. In conclusion, these two cases, in addition to the one other in the literature, suggest that collagenous colitis and ulcerative colitis may represent extremes in the spectrum of inflammatory bowel disease and that collagenous colitis may evolve to ulcerative colitis. Therefore, progression to ulcerative colitis should be considered in any patient with known collagenous colitis whenever bloody diarrhea occurs, or if red cells, as well as white cells, are noted on stool microscopy.

Superior oblique palsy in a patient with a history of perineural spread from a periorbital squamous cell carcinoma.

A 74-year-old man experienced vertical diplopia. Two years earlier, he was diagnosed with a squamous cell carcinoma of the periorbital frontal skin, with perineural spread involving the ophthalmic division of the right trigeminal nerve and the right facial nerve. The clinical findings were consistent with a right fourth cranial nerve palsy. Computerized tomography and magnetic resonance imaging demonstrated a discrete mass involving the belly of the right superior oblique muscle. An anterior orbitotomy and biopsy demonstrated a mass extending into the belly of the superior oblique muscle. Histology revealed an infiltrating squamous cell carcinoma. The possibility of perineural, direct, or metastatic spread to the superior oblique muscle should be considered in a patient with a history of squamous cell carcinoma of the head and neck. The authors believe this case to be the first report of superior oblique underaction due to involvement of the muscle by squamous cell carcinoma, presumably because of perineural spread. Diagnosis was made possible by neuroimaging and histopathology. There was good short-term resolution of the patient's diplopia after radiotherapy.

Pilomatrix carcinoma of the scalp.

A matrical carcinoma (pilomatrix carcinoma) of the scalp is described--the first reported case in this site. This malignant hair follicle tumour must be distinguished histologically from benign pilomatricoma and proliferating trichilemmal tumour, which can have similar features.

Thin-membrane nephropathy--a common cause of glomerular haematuria.

Thin-membrane nephropathy recently has been described as a cause of glomerular haematuria. The prognosis of the condition is unclear but it generally is considered to be benign. In a series of 92 patients with glomerular haematuria, thin-membrane nephropathy was found to be a common cause, occurring in 26 (28%) patients. Sixteen patients were women. The mean age was 42 years. Four patients had a family history of renal disease or haematuria and no patient was deaf. Haematuria had been present from six days to 30 years. Loin pain occurred in 31% of patients. Hypertension was not a feature and mild renal impairment was present in one case only, while a further three cases showed proteinuria at a level of greater than 500 mg of protein per day. Glomerular basement membranes in patients with thin-membrane nephropathy gave a mean (+/- standard deviation) width of 319 + 37 nm which was significantly (P less than 0.002) less than the control value of 394 +/- 61 nm. On the basis of clinical features and serological parameters, thin-membrane nephropathy could not be separated from other renal causes of haematuria but required careful electronmicroscopic examination of renal biopsy material to establish the diagnosis. Limited follow-up has confirmed the good prognosis of the condition.

Metastatic tumours of the parotid region.

Metastatic disease in the parotid gland and its associated lymph nodes is generally thought to be uncommon. A review of 121 cases was undertaken to study the incidence, histology and prognosis of secondary malignancy in the parotid region. Forty-two per cent of the cases were secondary malignancies. The majority of these were squamous cell carcinoma, and in this group the prognosis was poor.

Adenoid cystic carcinoma of the breast.

Adenoid cystic carcinoma is a rare malignant tumour of the breast. It usually presents as a painful, apparently benign lump near the nipple. The tumour has an interesting histology, natural history and mammographic appearance. Mastectomy is usually curative.