SUBCUTANEOUS MUCORMYCOSIS CAUSED BY RHIZOPUS ORYZAE PROBABLE NOSOCOMIAL ACQUIRED INFECTION (*) Flávio de QUEIROZ TELLES FILHO (1,4), Affonso COELHO (3), Edward PORTO (3) Rosângela Ferreira LAMEIRA (4), Marli Maria FREITAS (5), Jânio BARBOZA (5) and Jorge Luiz Zanette RAMOS (5) SUMMARY The Authors present a case of subcutaneous mucormycosis occurring in a patient with clinical and biochemical evidence of diabetic ketoacidosis. The clini­ cal, mycological and histopathological features are described, emphasizing the relevance of a rapid diagnosis in order to stablish early treatment. The clinical forms of mucormycosis and the main associated conditions are briefly reviewed as well as the most probable conditions which may lead to the enhanced suscep­ tibility to infection in the diabetic patient in ketoacidosis. The recovery of Rhizo¬ pus oryzae from the air of the room of the patient suggests a nosocomial infec­ tion acquired through contamination of venous puncture site by air borne spores. INTRODUCTION The human infections caused by fungi of as subcutaneous zygomycosis or basidiobolomy- the class Zygomycetes are cosmopolitan and cosis is restricted to tropical and subtropical re­ have been reported in normal and immunocom­ gions, being reported the cases mainly from promised hosts. The disease has been generi- Africa and Asia, and occasionally from South cally called Zygomycosis (Phycomycosis). America5.13.18. Generally it has a chronic evo­ GREER 12 suggested the terms Mucormycosis lution characterized by the development of eosi­ and Entomophtoromycosis to name the infec­ nophilic granuloma in the subcutaneous fat, rhi­ tions restrictly caused by Zygomycetes of the no-orbital cavities and other areas of the orga­ orders Mucorales and Entomophtorales, since nism, with swelling of the affected regions. The 12 they are different diseases . The human mu­ patients are apparently healthy6.18.19. cormycosis is world-wide in distribution often as an opportunistic infection and rarely affecting The agents of mucormycosis are ubiquitous immunologicaly normal individuals18. Frequen­ in nature, where they live on decaying organic tly it is a disease of acute evolution, characte­ material as saprophytes. They may be isola­ rized by invasion and growth of Mucorales in ted from the air, soil, fruits, clinical materials the vascular wall and lumen, with subsequent and human orifices4. They reproduce by se­ mycotic thromboembolism, ischemia, tissue ne­ xual and asexual ways and in the anamorphic crosis and eventually death depending on the (asexual) state form a great amount of spores effected site. The rhinocerebral variant is the inside sacular structures called sporangia. The most acute and fulminant of the known my­ principal way of dissemination is the air. The 21 cosis .22. The entomophtoromycosis, also known genera of the order Mucorales related as the (*) Hospital de Clínicas da Faculdade de Medicina da Universidade Federal do Paraná, Curitiba, PR, Brasil (1) Professor Auxiliar da Disciplina de Doenças Infecciosas e Parasitarias da U.F.PR (2) Professor Titular de Anatomia Patológica da U.F.PR (3) Micologista do Instituto de Medicina Tropical de São Paulo (4) Setor de Micologia Médica do Hospital de Clínicas da U.F.PR (5) Médicos Residentes do Departamento de Clínica Médica da U.F.PR cause of mucormycosis are the following: Rhi- he was conscious and the ketoacidosis was par­ zopus, Mucor, Absidia, Rhizomucor, Mortierella, tially corrected. On the fourth day there was Cunninghamella, Saksenaea and Syncephalas- a hemorragic and vesicular lesion on the left trum. forearm in the area where a venous puncture for fluid and electrolytes administration was The first case of mucormycosis, according done. This area was involved with elasticized to RIPPON22, was reported by PALTAUF in tape dressing. At the same time the patient 1885. There are approximately 400 cases of developed ketoacidosis again. In 24 hours the different clinical manifestations actually descri­ forearm lesion progressed to an extensive fage- bed. During the last two decades there was a denic ulceration with irregular margins, show­ significant increase in number mainly related ing the muscle tendons and measuring 12 x 8 to diabetic ketoacidosis and immunodepres¬ cm (Fig. 1A). A fragment to the margin was re­ sion ".".a. moved and sent to bacteriological, mycological The primary or exogenous cutaneous and and histopathological examination. subcutaneous mucormycosis is a rare occurren­ Bacteriology — Bacterial cultures of the ul­ ce and the way of infection is related to the ceration showed Staphylococcus aureus growth. rupture of the skin barrier with subsequent development of necrotic lesions in the skin or Mycology — The tissue fragment was sec­ subcutaneous iati5.2i. Recently microepidemics tioned in asseptic conditions and small portions of cutaneous mucormycosis were reported in were mounted in 40% potassium hydroxide on hospitals and were related to the use of elasti- a microscope slide and covered with a cover cized adhesive tape dressings on open wounds slip. Fragments were also placed in Petri dishes in immunocompromised patients 1U3 as well with Sabouraud's agar/cloramphenicol and in­ in patients with orthopedic problems and cubated at 37°C and room temperature (25°C). whithout apparent immunological change9. The reports with histological study and mycologi- Direct microscopic examination: after 15 mi­ cal identification, especially in hospital acquir­ nutes of tissue digestion a mass of intertwin­ ed cases are rare. ed hyphae were seen among the cell clusters in decomposition. After 4 hours, with better cla­ REPORT OF THE CASE rification, there was a great amount of thick, hyaline tortuous, coenocytic right-angled hyphae, A.S.F., 61 years old, white, male, diabetic, with no perfect parallel walls suggesting tissue was admitted to the emergency room of "Hos­ invasion by Mucorales. pital de Clinicas da Universidade Federal do Pa­ rana", in keto-acidotic coma. He was decom­ Culture — After 24 hours in all incubated pensated because of irregular use of insulin, plates the tissue fragment and the area of agar irregular diet and two abscesses in the left 3 cm around were covered by clear web like thigh. He was comatous, dehydrated, with the mycelium with radiated margins. At the mi­ following laboratory findings: Red blood cell croscope (400x) it seemed steril with an in­ count, 4,040,000/mm3; total white blood cell tense cytoplasmatic flux inside the coenocytic count, 10,700/mm3 and a differential count as hyphae. After 4 days the plates were totally follows: polymorphonuclear leukocytes, 77%; covered by an elevated cotton-like; brownish- lymphocytes, 20%; and monocytes, 3%. Blood gray mycelium with small dark points. The sli­ urea nitrogen 34 mg/lOOml; serum creatinin, de culture showed sporangia with no or sligh­ 3.8 mg/100 ml; blood glucose 694 mg/100 ml. tly branching, emerging in opposition to poor Serum electrolyte estimation showed the follow­ develloped rhizoids, which is characteristic of ing levels: sodium, 136 mEq/1; potassium, 4.6 Rhizopus sp. mEq/1. Arterial gases: pC02, 8.2 mmH20; pO,, 123 mmH20; buffer base, 16; base excess -32; Incubated samples in different temperatu pH 6.84; HC03 1,4 jttEg/1. res showed a positive growth at 45°C. Further subcultures were sent to Prof. Edward Porto, He was routinely treated and the abscesses "Instituto de Medicina Tropical de São Paulo", were drained. On the second day of admission who identified the Mucorales as Rhizopus arrhi- ms. This fungus is now considered as synonym Inflammation. Scattered among the polymor­ ol II. oryzae WENT & PRIM SEN GEHLIGS. phonuclear neutrophils were numerous broad 1895. non septated right angled branching hyphae IILslopatlioIORy — There was extensive ne­ easily recognized in the hematoxylin cosin stain­ crosis of skin and subcutaneous fat with acute ed slides <Fig. 1, C, Dh Special staining by Grocott methenamine silver nitrate technique DISCUSSION emphasized the contrast between the fungus and the tissue. There was no vascular invasion in According to reports on mucormycosis2, sections. the primary invasion of the skin and subcuta­ neous tissue by Mucorales occurs in less than Evolution — After the results from the 10% of the cases. Due to the possibility of in­ direct mycological examination, the patient re­ ternal dissemination from primary skin le­ ceived amphotericin B by venous route and sions 15'21, the disease must be promptly recog­ local therapeutics with 1.5% amphotericin B nized accordingly, and treated. In the case of cream. After completing 75 mg of systemic ad­ ketoacidosis associated with rapidly progressi­ ministration the diabetes was compensated, ve skin ulceration, the direct microscopical exa­ showing blood glucose of 173 mg/100 ml and mination with potassium hidroxide is conclusi­ normal arterial gases. The tissue specimens ve for treatment. When correctly interpreted still showed the presence of hyphae on histo­ the direct examinations allows the institution logical and mycological examinations. After of therapeutics until the tissue invasion is con­ completing 725 mg of amphotericin B the levels firmed by biopsy. The isolation of Mucorales of blood urea and serum creatinin were ele­ in culture, without evidence in the direct or vated and the drug was interrupted. The dia­ histopathological examination may only indica­ betes again showed ketoacidosis. After correct­ te a fungal contamination. ing the ketoacidosis and the reintroduction of amphotericin B, a